Microsoft® Exchange Online is a hosted messaging solution that delivers the capabilities of Microsoft Exchange Server as a cloud-based service. It gives users rich and familiar access to email, calendar, contacts, and tasks across PCs, the web, and mobile devices. With Exchange Online, organizations can take advantage of sophisticated messaging capabilities without the operational burden of on-premises server software.
This document provides information technology (IT) professionals with an overview of the capabilities of the Exchange Online service. To obtain detailed technical information about Exchange Online, please refer to the documentation available at http://help.outlook.com, especially the resources found on the help page Manage Your Organization – Office 365 for enterprises.
Features of Microsoft Office 365
Exchange Online is one of several cloud services offered by Microsoft Office 365 for enterprises. These Internet-based services are designed to help meet the need for robust security, 24/7 reliability, and user productivity.
Each service is designed for reliability, availability, and performance with a financially backed service level agreement (SLA) for a guaranteed 99.9-percent scheduled uptime. Microsoft deploys patches, security updates, and back-end upgrades, helping to eliminate the time and effort organizations spend managing their servers.
Subscribers to Exchange Online benefit from a set of features that are common to all of the Microsoft business-class cloud services:
- Secure access: Each offering from Microsoft Office 365 is accessed through 128-bit Secure Sockets Layer (SSL) or Transport Layer Security (TLS) encryption. Anyone who intercepts a communication sees only encrypted text.
- Intrusion monitoring: Microsoft continuously monitors the Office 365 systems for any unusual or suspicious activity. If Microsoft detects such activity, it investigates and responds appropriately. In the unlikely event that a significant incident occurs, the customer is notified.
- Security audits: Microsoft regularly assesses the Office 365 infrastructure to ensure that the latest antivirus signatures and required security updates are installed, and that high-level configuration settings are in compliance with Microsoft security policies. For details, refer to the Security and Service Continuity for Enterprises Service Description.
- High availability: Microsoft Office 365 services have a 99.9-percent scheduled uptime. If a customer’s service is affected, Office 365 offers financial remedies subject to the terms and conditions of the SLA. For details, refer to the Service Level Agreement for Microsoft Online Services.
- Service continuity: Redundant network architecture is hosted at geographically dispersed Microsoft data centers to handle unscheduled service outages. Data centers act as backups for each other: If one fails, the affected customers are transferred to another data center with limited interruption of service.
- Microsoft Online Services Portal: This easy-to-use website is the center for activities related to Microsoft Office 365. The portal provides services based on each organization’s specific needs. Prospective subscribers can use the portal to sign up for a free trial. End users accessing the portal can find online help, open Microsoft SharePoint site collections, and launch Microsoft Outlook® Web App. Administrators can manage users, administer services, download tools, and learn about service administration from online help.
- Directory Synchronization tool: For subscribers with Active Directory® directory services deployed on-premises, this tool helps keep the on-premises Active Directory and the Microsoft Office 365 directory synchronized.
- Remote administration: With Microsoft Windows PowerShell™, administrators can perform many tasks using a script or automated process. For example, tasks such as creating users, resetting passwords, assigning licenses, and obtaining service-use data can be fully automated.
Office Desktop Setup
For the best experience with Office 365, a set of required components and updates must be applied to each workstation. To simplify the installation and maintenance of these components and updates, Microsoft provides an installable piece of software—called Office desktop setup—at no charge. These updates are required for all workstations that use rich clients (such as Microsoft Office 2010) and connect to Microsoft Office 365.
Office desktop setup provides multiple benefits, including:
- Automatically detecting necessary updates.
- Installing updates and components upon approval or silently from a command line.
- Automatically configuring Outlook and Microsoft Lync for use with Microsoft Office 365.
- Uninstalling itself from the client computer after running.
A list of these update requirements are available for companies that want to use an alternative method of deploying the updates. See the help topic Manually update and configure desktops for Office 365 for details.
Note Office desktop setup is not an authentication or sign-in service and should not be confused with single sign-on.
Federated Identity and Single Sign-On
With on-premises Active Directory, administrators can use a single sign-on approach to Office 365 authentication. To achieve this, administrators can configure on-premises Active Directory federation Services—a Microsoft Windows Server® 2008 service—to federate with the Microsoft Federation Gateway. After Active Directory Federation Services is configured, all Office 365 users whose identities are based on the federated domain can use their existing corporate logon to automatically authenticate to Office 365.
Operating System and Software Requirements
Table 1 shows the operating system and browser combinations that are required to access Microsoft Office 365 services—including Exchange Online.
Table 1: Operating systems and browser combinations supported by Microsoft Office 365
Operating system Supported browers Windows 7 (32-bit)
- Windows Internet Explorer 8 and later versions
- Firefox 3 and later versions
- Chrome 6 and later versions
Windows 7 (64-bit)
- Internet Explorer 8 and later versions
- Firefox 3 and later versions
- Chrome 6 and later versions
Windows Vista with Service Pack 2 (32-bit)
- Internet Explorer 7 and later versions
- Firefox 3 and later versions
- Chrome 6 and later versions
Windows Vista with Service Pack 2 (64-bit)
- Internet Explorer 8
- Internet Explorer 7
- Firefox 5
Windows XP with Service Pack 3 (32-bit)
- Internet Explorer 7 and later versions
- Firefox 3 and later versions
- Chrome 6 and later versions
Windows XP with Service Pack 2 (64-bit)
- Internet Explorer 8
- Internet Explorer 7
- Firefox 5
Windows Server 2008 and Windows Server 2008 R2
- Internet Explorer 8 and later versions
- Firefox 3 and later versions
- Chrome 6 and later versions
Mac OS X 10.5 or Mac OS X 10.6
- Firefox 3 and later versions
- Safari 4 and later versions
Table 2 identifies other software required for using Office 365 services.
Table 2: Software supported by Microsoft Office 365
Software Supported Version System software
- Microsoft .NET Framework 3.0 (for Windows XP)
- Java client 1.4.2 (for Macintosh OS X)*
- Microsoft Office 2010 or Office 2007 Service Pack 2
- Office 2008 for Mac and Microsoft Entourage® 2008 Web Services Edition
- Office 2011 for Mac and Outlook 2011 for Mac
- Outlook 2003 via POP and IMAP only
- POP and IMAP protocols offer email-only access with a substantially reduced set of functionality
- Microsoft Lync 2010 client
- .NET Framework 2.0 or later
Client applications Office desktop set up Browser software for Microsoft Online Services Portal
- Internet Explorer 7 or later
- Mozilla Firefox 3.x
- Apple Safari 3.x
Browser software for
Outlook Web App
- Internet Explorer 7 or later
- Firefox 3 or later
- Safari 3 or later on Macintosh OS X 10.5
- Chrome 3 and later versions
Outlook Web App also has a “light” version that supports a reduced set of features across almost any browser
Office 365 is available in Austria, Belgium, Canada, Colombia, Costa Rica, Cyprus, Czech Republic, Denmark, Finland, France, Germany, Greece, Hong Kong, Hungary, India, Ireland, Israel, Italy, Japan, Luxembourg, Malaysia, Mexico, Netherlands, New Zealand, Norway, Peru, Poland, Portugal, Puerto Rico, Romania, Singapore, Spain, Sweden, Switzerland, Trinidad and Tobago, United Kingdom, and United States.
Multinational customers that purchase services in an approved country may enable use by their end users that reside anywhere in the world, except for countries currently embargoed by the U.S. government. Features availability may vary by location. See the help topic License restrictions for Office 365 for details.
Data Center Locations
Microsoft Office 365 maintains primary and backup data centers distributed around the world. When a company signs up for a Microsoft Office 365 service, its hosted environment is automatically provisioned in the appropriate data center based on the company’s address. All users for the company are hosted from the same region.
Table 3 summarizes the languages supported the Microsoft Office 365 platform and related components.
Table 3: Supported languages for components related to Microsoft Office 365
Component Supported languages Microsoft Online Services Portal Brazilian Portuguese, Chinese Traditional, Czech, Danish, Dutch, English, Finnish, French, German, Greek, Hungarian, Italian1, Japanese, Norwegian (Bokmal), Polish, Romanian, Spanish, Swedish Help content—for end users and IT professionals Brazilian Portuguese, Chinese Traditional, Czech, Danish, Dutch, English, Finnish, French, German, Greek, Hungarian, Italian, Japanese, Norwegian (Bokmal), Polish, Romanian, Spanish, Swedish Directory Synchronization Tool Brazilian Portuguese, Chinese Traditional, Czech, Danish, Dutch, English, Finnish, French, German, Greek, Hungarian, Italian, Japanese, Norwegian (Bokmal), Polish, Romanian, Spanish, Swedish
The Microsoft Office 365 technical support team provides supports services to people with administrator permissions for their company’s Office 365 services. Those with administrator permissions provide support services to their company’s Office 365 end users. For contact information, see Online Help in the services Administration Center.
Exchange Online Service Details
This section describes features included with the Microsoft Exchange Online service.
Exchange Online Client Languages
The client languages supported by Exchange Online are the same as those supported in Exchange Server 2010 Service Pack 1.
- For languages supported by Microsoft Outlook Web App, see the TechNet article Client Languages for Outlook Web App.
- For languages supported by Outlook, see the TechNet article Client Language Support for Outlook.
- For languages supported by Exchange Unified Messaging, see the TechNet article Client Language Support for Unified Messaging.
Exchange Online Administration Languages
The administration interfaces for Exchange Online are the same as those supported in Exchange Server 2010 Service Pack 1:
- For languages supported by Windows Remote PowerShell (also called the “Exchange Management Shell”), see the TechNet article Language Support for Exchange Management Interfaces.
- The languages supported by Exchange Control Panel are the same as those supported in Outlook Web App, see the TechNet article Client Languages for Outlook Web App.
Note The Microsoft Online Services Portal supports a different set of languages, as described earlier in this document.
Each user who accesses the Exchange Online service requires must be assigned to a subscription plan. Exchange Online offers three types of plans: Exchange Online Kiosk, Exchange Online (Plan 1), and Exchange Online (Plan 2).
Table 4 summarizes differences between the types of subscriptions.
Table 4: Overview of user subscriptions
Mailbox size 1 gigabyte (GB) 25 gigabytes (GB)* Unlimited** Outlook Web App
(regular and light versions)
Yes Yes Yes POP Yes Yes Yes IMAP No Yes Yes Outlook Anywhere (MAPI) No Yes Yes Microsoft Exchange ActiveSync Yes Yes Yes Exchange Web Services No*** Yes Yes Inbox rules No Yes Yes Delegate access No (cannot access other users’ mailboxes, shared mailboxes, or resource mailboxes) Yes Yes Instant messaging interoperability in OWA No Yes (requires Lync Online or Microsoft Lync Server 2010) Yes (requires Lync Online or Microsoft Lync Server 2010) SMS notifications No Yes Yes Custom retention policies Yes Yes Yes Multi-mailbox search Yes Yes Yes Personal archive No Yes Yes Voicemail No No Yes Legal hold No No Yes
*25 GB of storage apportioned across the user’s primary mailbox and personal archive
**25 GB of storage in the user’s primary mailbox, plus unlimited storage in the user’s personal archive. Refer to the personal archive section of this document for further information regarding unlimited storage in the archive
***Direct access to Kiosk user mailboxes via Exchange Web Services is not permitted. However, line of business applications can use Exchange Web Services impersonation to access Kiosk user mailboxes
All subscriptions include organization-wide capabilities such as journaling, transport rules, and premier anti-spam and antivirus filtering via Forefront Online Protection for Exchange.
User subscriptions are not required for conference rooms and shared mailboxes. These special mailbox types do not have login credentials—instead, licensed users with the appropriate permissions manage them via delegation.
Office 365 Suite Subscription Plans Exchange Online plans can be purchased on a standalone basis or as part of an Office 365 suite. Each Office 365 plan contains one of the Exchange Online plans. Tables 5 and 6 summarize the relationship between Exchange Online plans and Office 365 plans. To determine which plan is right for you, visit the Office 365 home page.
Table 5: Office 365 subscription plans for kiosk workers
Office 365 (Plan K1) Office 365 (Plan K2) Exchange Online Kiosk Exchange Online Kiosk SharePoint Online Kiosk SharePoint Online Kiosk Office Web Apps
Table 6: Office 365 subscription plans for information workers
Office 365 (Plan E1) Office 365 (Plan E2) Office 365 (Plan E3) Office 365 (Plan E4) Exchange Online (Plan 1) Exchange Online (Plan 1) Exchange Online (Plan 2) Exchange Online (Plan 2) SharePoint Online (Plan 1) SharePoint Online (Plan 1) SharePoint Online (Plan 2) SharePoint Online (Plan 2) Lync Online (Plan 2) Lync Online (Plan 2) Lync Online (Plan 2) Lync Online (Plan 2) Office Web Apps Office Web Apps Office Web Apps Office Professional Plus Office Professional Plus Lync Voice & PBX (Lync Plus CAL for Lync Server)*
* Lync Voice & PBX are only available with Lync Server 2010, deployed on-premises or hosted via a private cloud deployment. All Lync workloads (instant messaging, online meetings and Voice & PBX) must be deployed on Lync server in this case. It is not possible to split Lync workloads between Lync Server and Lync Online.
Mailbox Size Limits
The amount of mailbox storage available to a user is determined by his or her user subscription license:
- Each Exchange Online Kiosk user receives 1 GB of mailbox storage. The maximum mailbox size for a Kiosk user is 1 GB.
- Each Exchange Online (Plan 1) user receives 25 GB of mailbox storage, which can be split between the user’s primary mailbox and the user’s personal archive.
- Each Exchange Online (Plan 2) user receives 25 GB of storage in the user’s primary mailbox. The maximum size of the primary mailbox is 25 GB. The user also receives unlimited storage in the user’s personal archive (see the personal archive section of this document for details).
Administrators can use Remote PowerShell to reduce maximum mailbox sizes for some or all of their users. This is achieved by adjusting the mailbox capacity alerts described in the following paragraphs.
Special mailbox types, such as conference rooms and shared mailboxes, have different size limits. These limits are detailed in the relevant sections of this document.
Mailbox Capacity Alerts
Exchange Online provides three notifications to users as their primary mailboxes approach maximum size limits:
- Warning: Users receive email warnings when their mailboxes are approaching the maximum size limit. This warning is intended to encourage users to delete unwanted mail.
- Prohibit Send: Users receive email prohibit-send notifications when they reach their mailbox size limits. Users cannot send new messages until they delete enough messages so that their mailboxes are below the size limit.
- Prohibit Send/Receive: Exchange Online rejects any incoming mail when this limit is reached and then sends a non-delivery report (NDR) to senders. Sender can try resending the mail later. To receive messages, users must delete messages until the mailbox is below the size limit.
These values can be modified using Remote PowerShell, as described in the help topic Set Mailbox Quotas in Office 365 using Windows PowerShell. Table 7 shows the default values.
Table 7: Mailbox size limits and notifications
Mailbox type Warning Prohibit Send Prohibit Send/Receive Exchange Online Kiosk 0.92 GB 0.97 GB 1 GB Exchange Online (Plan 1) 24.5 GB 24.75 GB 25 GB Exchange Online (Plan 2) 24.5 GB 24.75 GB 25 GB
These limits and notifications are for the user’s primary mailbox. The personal archive has a separate, non-configurable quota.
Message Size Limits
Message size limits are necessary to prevent large messages from negatively affecting system performance and to ensure fast message delivery for all users. The message size limit for Exchange Online is 25 MB, including attachments. Messages larger than this limit will not be delivered, and the sender will receive a Non-Delivery Report (NDR). The message size limit is a global setting that applies to all messages (that is, inbound, outbound, and internal). This value cannot be adjusted up or down. However, administrators can create transport rules to limit the maximum size of any individual attachment.
Note An email client may limit the size of an individual file attachment to a value less than the message size limit.
To discourage users from sending unsolicited bulk messages, Exchange Online has restrictions that prevent users and applications from sending large volumes of email. Each Exchange Online mailbox can send messages to a maximum of 10,000 recipients per day. An email message can be addressed to a maximum of 500 recipients. These limits apply to emails sent within an organization as well as to messages delivered to external organizations.
Note For the purposes of these limits, a distribution group that is stored in the Global Address List counts as one recipient. In a personal distribution group, each recipient is counted separately.
See the help topic Recipient and sender limits for details.
Exchange Online customers who need to send legitimate bulk commercial email (for example, customer newsletters) should use third-party providers that specialize in these services.
Message Rate Limits
To prevent overconsumption of system resources and help guard against inappropriate use, users can send only 30 messages per minute. If a user submits messages at a faster rate, Exchange Online will deliver the messages but will queue the messages at the server and throttle the rate of delivery.
Additional limits relating to messages, mailboxes, and recipients help ensure the health and responsiveness of the Exchange Online service for all customers. To view these limits, go to the help topic Message and Recipient Limits.
Deleted Item Recovery
Exchange Online enables users to restore items they have deleted from any email folder. When an item is deleted, it is kept in a user’s Deleted Items folder. It remains there until it is manually removed by the user, or automatically removed by retention policies.
Note By default, retention policies will automatically remove items from the Deleted Items folder after 30 days, but organizations can customize these retention policies if desired. See the help topic Retention limits for details.
After an item has been removed from the Deleted Items folder, the item is kept in a Recoverable Items folder for an additional 14 days before being permanently removed. Users can recover these items using the Recover Deleted Items feature in Outlook Web App or Outlook.
If a user has manually purged an item from the Recoverable Items folder, an administrator can recover the item within the same 14 day window, through a feature called Single Item Recovery. This feature allows administrators to conduct a multi-mailbox search to find purged items and then use the search-mailbox PowerShell commandlet to move the items from the discovery mailbox to users’ mailboxes. See the help topic Recover Deleted E-mail Messages in Exchange Online for details.
Note The Single Item Recovery period is 14 days by default, but it can be increased to up to 30 days. As part of the most recent service update, most administrators should be able to configure the Single Item Recovery period through Remote PowerShell (RetainDeletedItemsFor). Some customers have not yet received this update and will need to continue contacting Office 365 support to make this adjustment.
Single Item Recovery can be disabled using Remote PowerShell. See the help topic Disable single item recovery for details.
If an administrator has placed a user’s mailbox on legal hold, purged items are retained indefinitely and the 14-day window does not apply.
Deleted Mailbox Recovery
When an Exchange Online mailbox is deleted, its contents are recoverable for 30 days. A recovered mailbox contains all of the data stored in it at the time it was deleted. After 30 days, the mailbox is not recoverable. Administrators can recover a deleted mailbox using the Exchange Control Panel.
If the mailbox was originally deleted from the Exchange Control Panel and the user’s account still exists in the Microsoft Online Services Portal, the administrator can recover the mailbox without assistance. If the user’s account was deleted from the Microsoft Online Services Portal, then a call to Office 365 support is required in order to restore the Microsoft Online account so it can be linked to the recovered mailbox.
When a shared mailbox is deleted, it is not listed in the Exchange Control Panel, and thus the contents are not recoverable.
See the help topic Recover a Deleted Mailbox for details.
Exchange Online mailboxes are replicated to multiple database copies, in geographically dispersed Microsoft data centers, to provide data restoration capability in the event of a messaging infrastructure failure. For large-scale failures, service continuity management is initiated.
Service Continuity Management
Exchange Online is hosted in Microsoft-managed, enterprise-level data centers that are designed to operate highly available online services. Exchange Online provides a financially-backed Service Level Agreement (SLA) with a 99.9 percent uptime guarantee.
Hardware failures, natural disasters, and human error all have the potential to affect service availability. To address this, Exchange Online offers service continuity management, a process for managing risks to ensure that the Exchange Online infrastructure is capable of providing continuing services if unexpected events occur. Service continuity management for Exchange Online includes provisions to quickly recover from these events.
Two metrics commonly used in service continuity management to evaluate disaster recovery solutions are a recovery time objective (RTO), which measures the time between a system disaster and the time when the system is again operational, and a recovery point objective (RPO), which is a time representation of the possible data loss that occurred as a result of the recovery from the unexpected event.
Exchange Online has set an RPO and RTO for client messaging services in the event of a disaster:
- Nearly instantaneous RPO: Microsoft protects your Exchange Online data and makes a nearly instantaneous copy of your data.
- 1 hour RTO: Organizations will be able to resume service within 60 minutes after service disruption if a disaster incapacitates a hosting data center.
The following conditions apply to service continuity management:
- Please see the Office 365 Identity Service Description for recovery times and other details related to sign-in and provisioning of new users and new tenants.
- Client access after recovery from a service disruption typically does not require reconfiguration on the part of Exchange Online subscribers.
- To achieve the stated recovery times, customer networking infrastructure must honor the DNS record Time to Live (TTL) of 5 minutes. Customers that have customized their client DNS settings and set a longer TTL may experience longer recovery times.
- After RPO and RTO objectives are met, there is a period of time before full data center redundancy is restored for the service. For example, Data Center 1 fails but services are restored by resources in Data Center 2. There may be a period of time until services in Data Center 2 have service continuity support either by restored resources in Data Center 1 or new resources in Data Center 3. Service Level agreements apply during this time.
You can obtain the most current information related to a service interrupting event by logging into the Service Health Dashboard at https://portal.microsoftonline.com.
Access to Exchange Online
Exchange Online allows users to connect to their mailboxes from a variety of devices and platforms. All network connectivity occurs over the Internet, and VPN connections are not required.
Note Microsoft reserves the right to block or throttle connections from any client software that negatively impacts the health of the Exchange Online service.
Microsoft Outlook is a rich email program that includes support for calendaring, contacts, and tasks. Exchange Online supports Microsoft Outlook 2010 and Microsoft Office Outlook 2007, including key features such as:
- Outlook Anywhere: Outlook Anywhere lets Outlook users connect to Exchange Online over the Internet with no need for a VPN connection. Communication between Outlook and Exchange Online occurs via an SSL-secured tunnel, using the RPC-over-HTTP Windows networking component.
- Exchange Autodiscover Service: The Exchange Autodiscover service automatically configures Outlook to work with Exchange Online. Autodiscover enables Outlook users to receive their required profile settings directly from Exchange Online the first time they sign in with their email address and password.
- Cached Exchange Mode: Cached Exchange Mode allows users to access local copies of their Exchange mailboxes when they are not connected to the Internet. Cached Exchange Mode maintains a client-side copy of users’ Exchange mailboxes in Outlook and automatically synchronizes this copy with the email server. In addition to providing offline access, it helps to provide a responsive user experience—even when network conditions between the client and the server are not ideal. Online Exchange Mode is also supported, but not recommended due to issues with latency inherent in Internet access.
- Offline Address Book: The offline address book is a snapshot of the Active Directory information available in the Global Address List. It is cached locally in Outlook to make it available when a user is working offline.
By default, Outlook access is enabled for all users. Administrators can disable access for specific users or groups through Remote PowerShell (Set-CASmailbox <Identity> –mapienabled $false).
Note Organizations are responsible for procuring, deploying, managing, and supporting Outlook. Outlook is not provided as part of the Exchange Online subscription price, although Microsoft Office Pro Plus is included in some Office 365 plans, and can be purchased as a separate subscription.
Outlook 2010 supports the latest features of Exchange Online, including:
- Conversation view and conversation actions (for example, Ignore, Always Move)
- Personal archive (this feature is available only in certain versions of Outlook 2010. See the Personal Archive section of this document for details).
- User-assigned retention policies
- Alerts for users on legal hold
- Meeting room finder
- Outlook Protection Rules (this feature requires Active Directory Rights Management Services)
- Protected voicemail (this feature requires Active Directory Rights Management Services)
- Voicemail preview
Note Some of these features are not available in previous versions of Outlook.
Outlook 2007 is supported for use with Exchange Online.
Outlook 2003 is only supported for use with Exchange Online via POP or IMAP. Using Outlook 2003 with POP or IMAP enables standard email functionality, but does have key limitations including:
- No calendar information
- No free/busy information
- No Global Address List
- No push email
- When connecting via POP, all messages will be downloaded to the client and there will be no synchronization between multiple computers or devices (such as between a laptop and a phone)
Outlook Web App
Microsoft Office Outlook Web App is a web-based version of the Outlook email program that is used with Exchange Online. Wherever users are connected to the Internet—at home, at the office, or on the road—they can access their email through Outlook Web App.
Outlook Web App is supported with full functionality on the following browsers:
- Internet Explorer 7 and later versions
- Firefox 3 or higher
- Safari 3 or higher on Macintosh OS X 10.5
- Chrome 3 and later versions
See the help topic Supported Browsers for Outlook Web App and Exchange Online for details.
The Light Version of Outlook Web App
The light version of Outlook Web App supports older web browsers and is optimized to support users who are blind or have impaired vision. Users can read and send messages, organize contacts, and schedule appointments and meetings in the light version of Outlook Web App. The light version can be used with almost any browser.
See the help topic Outlook Web App Light for details.
The Mini Version of Outlook Web App
The mini version of Outlook Web App allows users to access their mailboxes via a cHTML-compatible browser on simple feature phones.
Outlook Web App URLs
Users can access Outlook Web App from a link on the Microsoft Online Services Portal or at http://mail.office365.com. Administrators can provide users with customized URLs for accessing Outlook Web App (also known as “vanity URLs”) by using either of the following methods:
- Set up a CNAME record in DNS (for example, http://mail.contoso.com) that points to mail.office365.com.
- Redirect from a website (for example, http://contoso.com/OWA) to the standard Outlook Web App URL.
The exact procedure for redirecting users depends on where the domain name is registered or hosted.
Administrators can customize the Outlook Web App landing page if they have deployed Active Directory Federation Services 2.0 on-premises for single sign-on with Microsoft Office 365. In this case, the sign-in page is located on the on-premises servers, and the page can be customized. For example, usage guidelines or a disclaimer can be added for employees to view before logging on. The same logon page is used for Outlook Web App as well as other web-based Microsoft Office 365 applications.
If Active Directory Federation Services 2.0 is not deployed, a standard, non-customizable Outlook Web App sign-in page is displayed.
Public and Private Computer Sign-in Options
The Outlook Web App sign-in page does not offer Public Computer or Private Computer options.
By default, the Outlook Web App session time-out is six hours. The session time-out can be customized by using Remote PowerShell (set-OrganizationConfig –ActivityBasedAuthenticationTimeoutInterval).
WebReady Document Viewing
Outlook Web App features WebReady document viewing, which converts documents such as .pdf files into HTML for read-only viewing in a web browser window. When WebReady document viewing is enabled, users see an Open as Web Page link next to supported document types in Outlook Web App. By default, this feature is enabled in Exchange Online. It can be disabled through Remote PowerShell (set-OWAMailboxPolicy Default –WebReadyDocumentViewingOnPublicComputersEnabled $false).
Office Web App Attachment Preview
Outlook Web App now integrates the Office Web Apps into the attachment previewing experience for Microsoft Word documents, Microsoft Excel® spreadsheets, and Microsoft PowerPoint® presentations. When Office Web App attachment preview is enabled, users see an Open In Browser link next to the Office Web App document type in Outlook Web App. By clicking on the link, the user can open the attached document using the Office Web Apps to get a high-fidelity preview of the Office document in a web browser window. By default, this feature is enabled in Exchange Online. It can be disabled through Remote PowerShell (Set-OwaMailboxPolicy Default -WacViewingOnPublicComputersEnabled $false –WacViewingOnPrivateComputersEnabled $false). Preventing Attachment Downloads
Administrators can block users from downloading attachments in Outlook Web App. This helps prevent users from accidentally leaving content on an unsecure machine, such as an Internet kiosk. Attachment download settings in Outlook Web App are managed through Remote PowerShell (Set-OwaMailboxPolicy Default -DirectFileAccessOnPublicComputersEnabled $false).
Outlook Web App Customization
Administrators can use Outlook Web App mailbox policies to enable and disable specific features within Outlook Web App, such as calendaring, contacts, Global Address lists, and tasks. Administrators can customize these settings through Remote PowerShell (set-OWAMailboxPolicy) and apply the custom Outlook Web App settings to all users or a subset of users.
Outlook Web App includes a number of built-in themes that users can select to customize the look and feel of the Outlook Web App interface. However, there is no option to customize the Outlook Web App header with an organization’s logo or color scheme.
Users and administrators cannot customize the Outlook Web App interface by adding links, buttons, or custom forms because this type of extensibility would require adding and editing files on Client Access Servers in the Exchange Online infrastructure.
Disabling Outlook Web App Access
Administrators can disable access to Outlook Web App on a per-user basis through Remote PowerShell (set-CASmailbox <Identity> -OWAEnabled $false).
Changing Passwords from Outlook Web App
If an organization is using Active Directory Federation Services 2.0 for single sign-on, users manage their credentials directly in their on-premises Active Directory. Users cannot change their passwords from Outlook Web App.
If an organization is not using Active Directory Federation Services 2.0 for single sign-on, the Outlook Web App Options page displays a link to a separate page where users can change their passwords for all Microsoft Online services.
Instant Messaging and Presence
Outlook Web App can interoperate with Lync Online and on-premises Lync Server 2010 to provide users with instant messaging (IM) and presence within the Outlook Web App interface. This capability is not available to users with Kiosk subscriptions, even if they have accounts in Lync Online or Lync Server.
IM and presence in OWA is enabled by default for users with active Lync Online accounts. To enable these features for users with on-premises accounts in Lync Server, administrators must configure an SRV record in DNS and install trusted certificates on local Lync servers. Administrators can disable IM and presence in OWA for individual users or for their entire organization by using Remote PowerShell (set-OWAMailboxPolicy Default –InstantMessagingEnabled $false).
Senders’ Photos in Outlook Web App
Outlook Web App incorporates photos of users stored in Active Directory as part of its user interface. For example, when users receive emails from coworkers, they can see the senders’ photos in the reading pane in Outlook Web App. When users search for coworkers in the Global Address List using Outlook Web App, the coworkers’ photos are displayed. Mobile devices that support the latest version of Exchange ActiveSync can also display photos from Active Directory. Outlook 2010 also includes new features that incorporate photos of users stored in Active Directory.
There are two ways to get user photos into the Exchange Online environment and enable these features:
- End users upload their photos manually through the User Settings screen in the Microsoft Online Portal.
- Administrators populate the ThumbnailPhoto user attribute in on-premises Active Directory; the Directory Synchronization tool will automatically synchronize the user photo to Exchange Online, SharePoint Online, and Lync Online.
Outlook Web App in Internet Explorer 9
Outlook Web App can be pinned to the Windows 7 taskbar using Internet Explorer 9 Pinned Sites. This gives users the ability to launch Outlook Web App with one click and run it with fewer distractions, separated from other browser sessions. It also keeps users informed of incoming email and instant messages when minimized or hidden and offers quick access to common Outlook Web App commands from the Windows 7 taskbar.
See the Windows topic Pinned Sites for details.
Microsoft Outlook for Mac 2011
Microsoft Outlook for Mac 2011 is a rich client for Macintosh users that provides email, calendaring, an address book, a task list, and a note list. Exchange Online supports Outlook for Mac 2011.
Note Organizations are responsible for procuring, deploying, managing, and supporting Microsoft Outlook for Mac 2011.
Microsoft Office Entourage 2008 Web Services Edition
Exchange Online supports Microsoft Entourage 2008 Web Services Edition, which is available as free update to users of Entourage 2008.
Note Organizations are responsible for procuring, deploying, managing, and supporting Entourage 2008 Web Services Edition.
Exchange Online supports mailbox access through the IMAP4 protocol. IMAP is enabled by default for all users except those with Kiosk subscriptions. Users can view their IMAP connection settings on the Outlook Web App Options page. Administrators can disable IMAP access on a per-user basis using Remote PowerShell (set-CASMailbox <Identity> -ImapEnabled $false).
Exchange Online supports mailbox access through the POP3 protocol. POP is enabled by default for all users, who can view their POP connection settings on the Outlook Web App Options page. Administrators can disable POP access on a per-user basis using Remote PowerShell (set-CASMailbox <Identity> -PopEnabled $false).
The SMTP protocol is used to send outbound mail for clients that connect to Exchange Online through IMAP or POP. Transport Layer Security (TLS) encryption and authentication is required when using SMTP to send email. SMTP is also used by applications that send email. Refer to SMTP Relay in the Application Interoperability section of this document for details.
Exchange ActiveSync (Mobile Devices)
Exchange Online supports the Microsoft Exchange ActiveSync protocol. Exchange ActiveSync provides synchronization of mailbox data between mobile devices and Exchange Online, so users can access their email, calendar, contacts, and tasks on the go.
Exchange ActiveSync is supported by a wide range of mobile devices, including Microsoft Windows Mobile® and Windows Phone, Nokia E and N series devices, Palm devices, Apple iPhone and iPad, and certain Android phones. Implementation of specific Exchange ActiveSync features varies by device and manufacturer. A community-maintained comparison of how Exchange ActiveSync features are implemented by various mobile clients is available at this Comparison of Exchange ActiveSync Clients page.
The Exchange ActiveSync Logo Program helps organizations identify enterprise-ready mobile devices that have implemented key Exchange ActiveSync user features and management policies. A list of Exchange ActiveSync Logo Program Qualified Devices is available in the TechNet article Exchange ActiveSync Logo Program.
Note Organizations are responsible for procuring, deploying, managing, and supporting mobile client software and compatible devices, as well as managing relationships with wireless carriers. Microsoft does not provide end-user device support.
Exchange Online supports the Exchange Autodiscover service. Mobile devices that support Autodiscover provide users with a simplified setup experience when connecting to Exchange Online. Users do not need to know the address of their email server when connecting their mobile device to Exchange Online—they simply enter an email address and password, and the device automatically obtains the additional server settings required to set up their mobile profile.
Remote Device Wipe
If users lose their mobile devices, they can remotely wipe the device of all data the next time the devices connect to Exchange Online. Users can trigger the remote wipe through the Outlook Web App Options page, or administrators can log on to the Outlook Web App Settings page to trigger the device wipe on behalf of the user. A confirmation message is sent to the users when the mobile devices acknowledge the remote wipe request.
Exchange ActiveSync Policies
Administrators can enforce security policies on mobile devices that connect to Exchange Online through Exchange ActiveSync. Administrators can customize these policies for specific users and groups within their company, using web-based graphical user interface (GUI) or Remote PowerShell. Exchange Online supports the same ActiveSync policies as Exchange Server 2010 Service Pack 1.
See the help topic Change an ActiveSync Device Policy for details.
Disable Exchange ActiveSync Access
Exchange ActiveSync access is enabled by default for all Exchange Online users. Administrators can disable Exchange ActiveSync access on a per-user basis through the web-based GUI in the Exchange Control Panel or through Remote PowerShell (set-CASMailbox <Identity> -ActiveSyncEnabled $false).
Allow, Block, and Quarantine Controls
Administrators can control which mobile device models and families can connect to the Exchange Online environment through Allow, Block, and Quarantine controls. Administrators can manage these controls through the web-based GUI in the Exchange Control Panel or through Remote PowerShell.
See the help topic Allow, Block, or Quarantine New Device Connections for details.
Certificate-based Authentication for Exchange ActiveSync
Exchange Online does not support certificate-based authentication for devices that connect via Exchange ActiveSync.
Exchange Online users can have text message alerts sent to their mobile phones when they receive email messages or meeting requests. Users who are enabled for hosted voicemail can also receive notifications of missed calls and voicemails. This feature does not require an Exchange ActiveSync device partnership. Users can set up these notifications on the Outlook Web App Options page.
This feature is currently available only to users in the United States, Canada, and Romania. It is not available to users with Exchange Online Kiosk subscriptions. Administrators can disable the feature on a per-user basis using Remote PowerShell (Set-OwaMailboxPolicy Default -TextMessagingEnabled $false).
Details on SMS notifications are available at the help topic Learn About Text Messaging.
BlackBerry Business Cloud Services (BBCS) is hosted by Research In Motion (RIM) and extends Exchange Online services to BlackBerry smartphones. Administrators are able to perform cloud-based provisioning and management of BlackBerry smartphones within this environment. BBCS utilizes familiar underlying RIM technology and functionality experienced with BlackBerry services and provides BlackBerry email, calendar, and personal information management experience for Exchange Online (Plan 1) and Exchange Online (Plan 2) users. See the BlackBerry Business Cloud Services (BBCS) Service Description for details.
Users of BlackBerry devices can also connect their devices to Exchange Online using the BlackBerry Internet Service (BIS). This service allows BlackBerry users to access their e-mail accounts without connecting through a BlackBerry Enterprise Server (BES). It does not provide the same capabilities as a BES server or a hosted BES service. Exchange Online (Plan 1) and Exchange Online (Plan 2) users can configure BIS to access their mailboxes via IMAP. Exchange Online Kiosk users can configure BIS to access their mailboxes via POP.
Email Features and Configurations
This section describes specific email features and configurations available with Exchange Online.
Delegate Access (Send on Behalf Permissions)
Exchange Online supports delegate access—that is, the ability for users to allow others to manage their email and calendars. Delegate access is commonly used between a manager and an assistant, where the assistant is responsible for processing the manager’s incoming email messages and coordinating the manager’s schedule. When delegates have Send on Behalf permissions, they can compose email messages and enter the manager’s name in the From field, where it will be displayed as “[delegate name] on behalf of [manager name]”. The ability to access other mailboxes via delegate access is not available to users with Exchange Online Kiosk subscriptions.
Users and administrators can set up and manage these delegate permissions using Outlook. For details on how Delegate Access works, see help topic Allow someone else to manage your mail and calendar.
Send As Permissions
Exchange Online supports advanced delegation scenarios, including Send As permissions. Send As permissions allow users to send messages from another mailbox as if they are the mailbox owner. This scenario is common where there is a shared mailbox and several employees send email messages from that shared mailbox instead of their Exchange accounts. The ability to access other mailboxes via Send As permissions is not available to users with Exchange Online Kiosk subscriptions.
Shared mailboxes allow a group of users to view and send e-mail from a common mailbox (for example, email@example.com or firstname.lastname@example.org). A shared mailbox does not have a username and password, so users cannot log on to it directly. They must sign in to their own mailboxes and then open the shared mailbox using Send As permissions.
Shared mailboxes do not need to be assigned to a subscription plan, but each user that accesses a shared mailbox must be assigned to a subscription plan. Users with Exchange Online Kiosk subscriptions cannot access shared mailboxes.
Each shared mailbox has a maximum size of 5 GB. If additional storage is required, the shared mailbox must be assigned an Exchange Online (Plan 1) or Exchange Online (Plan 2) subscription. If legal hold is required, the shared mailbox must be assigned an Exchange Online (Plan 2) subscription.
Shared mailboxes are subject to the same recipient limits and message rate limits as regular mailboxes. These limits are described in the Recipient Limits section of this document. A shared mailbox can be used to store emails sent to and received by the shared mailbox. It can also be used to store data migrated from on-premises public folders. A shared mailbox cannot be used to archive e-mails for individual users.
In Exchange Online, shared mailboxes are created only via Remote PowerShell. See the help topic Set Up a Shared Mailbox for details.
A catch-all mailbox receives messages sent to email addresses in a domain that do not exist. Exchange Online anti-spam filters use recipient filtering to reject messages sent to mailboxes that don’t exist, so catch-all mailboxes are not supported.
Exchange Online allows users to create inbox rules that automatically perform specific, criteria-based actions on messages as they arrive. For example, users can create a rule to automatically move all mail to a specific folder if the mail was sent to a certain distribution group. Inbox rules are managed from Outlook or Outlook Web App. Inbox rules are not available to users with Exchange Online Kiosk subscriptions.
See the help topic Learn About Inbox Rules for details.
In some situations, administrators may want to prevent users from setting up certain types of inbox rules. For example, they may want to disable server-side email forwarding so that users cannot automatically forward email to personal accounts. They may also want to disable server-side automatic replies—such as “Have Server Reply with Template Message”—so that these automatic replies cannot be used by outside parties to identify valid email addresses. Administrators can disable server-side forwarding and disable server-side automatic replies using Remote PowerShell (set-remotedomain -AutoReplyEnabled $false and –AutoForwardEnabled $false).
MailTips provide automated alerts that help users avoid embarrassing email mistakes. They appear above the To: line of an email to prevent accidental delivery or policy violations. For example, MailTips generate an alert if senders try to send messages to large groups or to groups that contain external recipients. MailTips also provide alerts when a user composes a message to a distribution group that is moderated or restricted. MailTips are available in Exchange Online to users who access their mailboxes from Outlook Web App or Outlook 2010.
See the help topic Configure MailTips for details.
For users who have multiple email accounts and want to interact with all their messages in one place, Exchange Online provides a feature called Connected Accounts. This feature lets users connect external email accounts to their Exchange Online accounts, and use Outlook Web App to send and receive mail from these connected accounts. Connected Accounts automatically synchronize upon log-in to Outlook Web App, and users can click on the refresh button in Outlook Web App to manually synchronize their Connected Accounts, This feature is not available in the on-premises edition of Exchange Server. Administrators can enable and disable this feature for specific users or all users, by adjusting the MyMailSubscriptions role in the relevant Role Assignment Policy, via the Exchange Control Panel.
Contacts and Distribution Groups
This section describes Exchange Online support for contacts and distribution groups.
A distribution group (or distribution list) is a collection of users, contacts, and other distribution groups that are available to all users in a company. A distribution group makes it easy to send messages to multiple people. Unlike personal distribution groups that individuals create in Outlook, these distribution groups are globally available. Distribution groups are created in the Exchange Control Panel or synchronized from on-premises Active Directory, and then appear in the Global Address List in Outlook.
Exchange Online supports advanced distribution group capabilities, including:
- Restricted distribution groups
- Dynamic distribution groups
- Moderated distribution groups
- Self-service distribution groups
See the help topic Change Distribution Group Properties for details.
Restricted Distribution Groups
By default, anyone can send emails to a distribution group. However, administrators can change the permissions of a distribution group to allow only specific individuals to send emails to that group. This restriction can discourage inappropriate use of large distribution lists. Administrators can also block external sources from sending email to distribution groups in order to prevent spam. Distribution group permissions can be managed via web-based GUI in the Exchange Control Panel and via Remote PowerShell. For distribution groups that are synchronized from on-premises Active Directory using the Directory Synchronization tool, the attributes for restriction are synchronized to the cloud automatically.
Dynamic Distribution Groups
The membership list for a dynamic distribution group (also known as a dynamic distribution list, or query-based distribution list) is calculated every time a message is sent to the group. This calculation is based on filters and conditions that the administrator defines. Dynamic distribution groups are supported in Exchange Online. They are managed through Remote PowerShell, and they do not appear in the web management GUI.
The Office 365 Directory Synchronization tool ignores dynamic distribution groups in on-premises Active Directory, and does not synchronize these to Exchange Online. Organizations that use the Directory Synchronization tool should use a naming convention that avoids conflicts between the regular distribution groups managed on-premises and the dynamic distribution groups that are managed in Exchange Online.
See the help topic Dynamic Distribution Groups for details.
Moderated Distribution Groups
Administrators can select a moderator to regulate the flow of messages sent to a distribution group. With moderated distribution groups, anyone can email the distribution group alias, but before the message is delivered to the members of the group, a moderator must review and approve it. This can help to prevent users from sending inappropriate emails to large audiences. Distribution group moderation can be managed in the Exchange Control Panel.
Self-Service Distribution Groups
Administrators can give users the ability to manage their own distribution group membership from an easy-to use, web-based interface. These self-service capabilities can help users be more productive and lighten the burden on an organization’s help desk. Users can be given permissions to:
- Create distribution groups
- Delete distribution groups
- Join or leave distribution groups
These capabilities are enabled by default for all Exchange Online users. Administrators can disable these self-service features and let the IT department manage distribution groups, if desired, by adjusting role assignment policies as described in the help topic Prevent Users from Creating Distribution Groups.
Administrators can also create group naming policies that allow them to standardize and manage the names of distribution groups created by users in their organizations. For example, a specific prefix or suffix can be added to the name of the distribution group when it is created and specific words can be blocked from being used to prevent the creation of inappropriate names. See the help topic Create a Naming Policy for Distribution Groups for details.
Self-service capabilities are not available for distribution groups that synchronized from on-premises Active Directory to Exchange Online. Organizations that use Directory Synchronization should use a naming convention that avoids conflicts between distribution groups managed on-premises and distribution groups managed in the cloud.
Global Address List
Exchange Online supports the Global Address List, an organization-wide directory of all mail-enabled users, distribution groups, and external contacts.
Administrators can hide users, distribution groups, and contacts from the Global Address List by setting the HideInAddressList attribute for the object in on-premises Active Directory (if using the Directory Synchronization tool) or through Remote PowerShell. See the help topic Hide a User from the Shared Address Book in Office 365 for details.
Custom Address Lists
Hierarchical address lists, Global Address List segmentation, custom Global Address List views, and multiple address lists per organization are not available in Exchange Online. For example, users cannot create address lists that put contacts from North America in one view and those from Europe in another view. Similarly, it is not possible to prevent users in one of an organization’s subsidiaries from viewing users in another subsidiary.
An external contact is a record with information about a person who works outside of a specified organization. External contacts are available to all users in an organization, which makes external contacts different from the personal contacts that individuals create in Outlook. External contacts are created in the Exchange Control Panel, created via Remote PowerShell, or synchronized from on-premises Active Directory. They appear in the Global Address List in Outlook.
See the help topic External Contacts in the Address Book for details.
Exchange Online calendar features are described in this section.
Out-of-office messages are automatic replies to incoming messages, sent by Exchange Online behalf of a user. Users can schedule out-of-office messages in advance, with specific start and end times and can format them as rich HTML messages with hyperlinks rather than plain text. Users can configure separate out-of-office messages for internal and external users. Junk email and mailing list awareness in Exchange Online prevents users from sending external out-of-office messages to extended mailing lists and people who send spam. Exchange Online also lets users set out-of-office messages from mobile devices that support this Exchange ActiveSync feature.
Administrators can prevent users from sending out-of-office messages to external users through Remote PowerShell (set-remotedomain –AllowedOOFType Internal).
Federated Calendar Sharing
Exchange Online customers can share free/busy calendar data with other organizations hosted by Exchange Online as well as with organizations running Exchange Server 2010 on-premises. Administrators do not need to set up a trust with the Microsoft Federation Gateway because this trust is pre-configured for all customers on the Exchange Online platform.
A Default Sharing Policy allows users to share basic free/busy data with users in other federated organizations, by sending calendar sharing invitations in OWA or Outlook 2010. Administrators can use Remote PowerShell to disable the Default Sharing Policy, as well as configure additional calendar sharing policies which specifies what level of free/busy calendar data users can share.
Administrators can also create an organization-to-organization relationship with another federated org, which allows the desired level of free/busy information for every user to be visible cross-org without the need for individual users to make a sharing invitation of any kind. Within the scope of administrator-defined Sharing Policies and/or org-org relationships, users can individually limit the detail of their sharing further.
See the help topic Configure Federated Delegation in the Cloud for details.
Calendar Sharing through iCal
Exchange Online allows users to publish their calendars using the iCal format for anonymous access by anybody, inside or outside the organization. Recipients can be using Exchange, another platform, or simply a web browser. Exchange Online users can also subscribe to calendars that others have published to Internet locations through iCal. This personal calendar sharing is different than federated calendar sharing, which is configured by an administrator and provides organization-to-organization free/busy sharing. No user can publish calendar data in iCal format until the administrator has set and applied a Sharing Policy that allows it. Administrators can disable iCal publishing and iCal subscriptions for users in an organization by changing their Sharing Policy through Remote PowerShell.
Conference Rooms and Resource Mailboxes
Conference room mailboxes represent a company’s meeting rooms or other facilities. Users can reserve rooms by adding the conference room email alias to meeting requests in Outlook or Outlook Web App. Conference rooms appear in the Global Address List in Outlook and Outlook Web App, and administrators can create conference rooms in the Exchange Control Panel or through Remote PowerShell. Administrators can also use the Directory Synchronization tool to synchronize conference rooms from on-premises Active Directory. The mailbox quota for conference rooms is 250 MB. Conference rooms do not require a user subscription license. Custom resource properties cannot be added to conference rooms in Exchange Online.
See the help topic Create a New Room Mailbox for details.
Resource Booking Attendant
Exchange Online includes the Resource Booking Attendant (RBA), which helps to automate the scheduling of conference rooms. A conference room mailbox uses the Resource Booking Attendant to automatically accept, decline, or acknowledge meeting requests based on its calendar availability. Through the Outlook Web App Options page, administrators can customize automated conference room responses and configure booking policies. These policies include who can schedule a conference room, when it can be scheduled, what meeting information is visible on the resource’s calendar, and what percentage of scheduling conflicts is allowed. Administrators can disable the Resource Booking Attendant and assign specific users to manually manage meeting requests for conference rooms.
See the help topic Resource Scheduling Options for details.
Outlook 2010 Room Finder
Exchange Online supports the Room Finder feature of Outlook 2010, which arranges rooms into lists (for example, a list called “Building 5 rooms”) to make it easier to find a nearby room when scheduling a meeting. To appear in the room list, a distribution group must be specially marked using one of two methods:
- A new room list can be created using Remote PowerShell (see the TechNet article Create a Room List Distribution Group).
- Any distribution group that contains only rooms can be converted to a room list through Remote PowerShell.
Voicemail and Fax Features
Exchange Online voice and fax features are presented in the sections that follow.
Hosted Voicemail (Unified Messaging)
Exchange Online offers hosted unified messaging services, which provide:
- Call answering (voicemail)
- Dial-in user interface to Exchange (Outlook Voice Access)
- Dial-in interface for callers (Automated Attendant)
Hosted unified messaging allows a company to connect its on-premises phone system to voicemail services provided by Exchange Online. Voicemails are recorded and stored in the Exchange Online infrastructure, allowing users to access their voice messages from Outlook, Outlook Web App, or mobile phones.
All telephony connections to Exchange Online require voice-over-IP (VoIP) protocols. Administrators can connect on-premises PBX phone systems to Exchange Online using VoIP media gateways and session border controllers (SBCs). A VoIP media gateway is not required if the PBX supports VoIP directly and is interoperable with Exchange unified messaging. SBCs are deployed in the perimeter of the customer network and help secure the communications (and the customer network) against eavesdropping and intrusion. Interoperability with the voice capabilities of Lync Server 2010 is also supported.
Note Currently, customers hosted from data centers in the Asia-Pacific region may experience higher latencies than expected when using Lync Server 2010 with hosted voicemail services. This issue will be resolved in upcoming updates to the service.
The unified messaging features available in Exchange Online are similar to those offered in Exchange Server 2010 Service Pack 1, except speech access to the directory is not supported in Exchange Online. Instead of speaking names, users must spell names using the touchpad when searching for someone in the directory by name in Outlook Voice Access or the company auto attendant. Speech access to Personal Contacts and Personal Distribution Lists is supported.
The following unified messaging features work similarly online and on-premises:
- Play on phone from Outlook and Outlook Web App
- Missed call notifications
- Caller ID (using information in the Global Address List and users’ Outlook contacts)
- Voicemail PIN reset from Outlook Web App and Outlook
- Message waiting indicator
- Call answering rules
- Protected voicemail (see the Information Rights Management subsection of this document for details)
- Voicemail preview (see the Client Languages subsection of this document for language support)
The Exchange Control Panel includes screens to configure and manage unified messaging interoperability. See the help topic Use Unified Messaging to Connect Exchange to Your Telephone System for complete details about hosted voicemail and unified messaging.
Interoperability with On-Premises Voicemail Systems
On-premises voicemail solutions from third-party providers can interoperate with Exchange Online if they can forward voicemails through SMTP or if they support Microsoft Exchange Web Services. If the voicemail system does not natively support forwarding voicemails through SMTP, an email server can be kept on-premises to receive messages from the voicemail system and then forward them to the cloud using SMTP. Because many third-party voicemail systems use MAPI/CDO to interoperate with Exchange Server for advanced unified messaging features, the full capabilities of these systems may not be available when SMTP is used for interoperability with Exchange Online.
Outbound Fax Services
Exchange Online does not provide outbound fax services. Solutions for outbound fax, including Internet-based fax services, are available from third-party providers. Generally, these outbound fax solutions are independent from an organization’s email infrastructure and require no special interoperability with Exchange Online.
Inbound Fax Services
Exchange Online does not provide inbound fax services. If an organization uses a third-party fax solution that is capable of receiving faxes and forwarding them to recipients via email, the administrator can specify Exchange Online mailboxes as a destination. If the organization has deployed Unified Messaging in Exchange Online, advanced interoperability with inbound fax solutions is available. This interoperability enables features such as one-number fax receiving (a single phone number for voice calls and fax), rich caller-ID information through Active Directory and Exchange personal contacts, and identification of fax messages as a special message class in Exchange and Outlook.
Exchange Online security features are presented in the sections that follow.
Anti-Spam and Antivirus Filtering
Exchange Online uses Microsoft Forefront® Online Protection for Exchange and Microsoft Forefront® Protection for Exchange Server to help protect incoming, outgoing, and internal messages from malicious software transferred through email.
This service uses proprietary anti-spam technology to help achieve high accuracy rates, and multiple, complementary antivirus engines to help detect viruses and other malicious code spread through email. Administrators do not need to set up, configure, or maintain the filtering technology because antivirus and anti-spam protections are preconfigured.
Administrators can manage advanced controls over anti-spam and email control settings directly through the Forefront Online Protection for Exchange (FOPE) Administration Center. See the Administration section of this document for more details.
Safe and Blocked Senders
Users can manage their safe and blocked senders from within their inboxes in Outlook or Outlook Web App. They can right-click any message and specify several actions, including:
- Block the sender.
- Never block the sender.
- Never block the sender’s domain (@example.com).
- Never block this group or mailing list.
They can also manage their advanced Junk Mail options and view complete lists of safe and blocked senders.
Administrators can manage organization-wide safe and blocked sender lists via the Forefront Online Protection for Exchange (FOPE) Administration Center, specifying the IP addresses, domains, or email addresses to allow or restrict.
Junk Mail and Spam Quarantine
When Exchange Online receives messages, they are evaluated and assigned a spam confidence level (SCL) value. Messages with low SCL values are delivered to users’ inboxes, and messages with borderline SCL values are placed in users’ Junk Mail folders in Outlook and Outlook Web App, where they are automatically removed after 30 days.
By default, no emails are kept in the Forefront Online Protection for Exchange (FOPE) spam quarantine and no FOPE spam digest emails are sent. This eliminates the need for administrators and users to log on to a separate quarantine. However, organizations can choose to use FOPE’s spam quarantine rather than the integrated Junk Mail experience in Outlook and OWA. Administrators can change the spam action settings for their organization by accessing the FOPE Administration Center and following the instructions at the TechNet article Spam Quarantine. If an error message appears when attempting to add an Office 365 administrator account as a FOPE user account in the FOPE Administration Center, refer to the Microsoft Support article Office 365 administrators cannot sign in to the FOPE Quarantine service to access mail quarantine for additional instructions.
Use of Other Filtering Services for Inbound Email
An on-premises appliance or another hosted service can be used to filter email before it reaches Exchange Online. In this scenario, the email domain’s MX record is pointed to the appliance or service, which then relays the email to Exchange Online. This same configuration can also be used in email coexistence, when some users have mailboxes in an on-premises email server while others are hosted in Exchange Online.
See the TechNet article Inbound Safe Listing Scenario for details.
Custom Routing of Outbound Email
Exchange Online provides the ability to route outbound mail through an on-premises server or a hosted service (sometimes called “smart hosting”). This capability allows organizations to utilize data loss prevention (DLP) appliances, perform custom post-processing of outbound e-mail, and deliver e-mail to business partners via private networks. Administrators configure custom e-mail routing within the Forefront Online Protection for Exchange (FOPE) Administration Center.
See the TechNet article Outbound Smart Host for details.
Some organizations modify outbound email to hide sub-domains, to make email from a multi-domain organization appear as a single domain, and to make partner-relayed email appear as if it were sent from inside the organization. Customers can route outbound email through an on-premises gateway to rewrite addresses in this way.
Transport Layer Security (TLS)
Transport Layer Security (TLS) is method of encrypting the connection between email servers to help prevent spoofing and provide confidentiality for messages in transit. TLS is also used for securing on-premises mail server traffic to Exchange Online during migration and coexistence.
Exchange Online supports opportunistic TLS for inbound and outbound email, and this feature is enabled by default. If the other party’s mail server has a public certificate that is trusted by Forefront Online Protection for Exchange and supports the starttls command, a TLS connection is automatically established between the servers. If TLS cannot be established, the server will still transmit the email, but the connection will not be encrypted.
Exchange Online supports forced TLS for outbound and inbound connections. Administrators can configure forced TLS on a per-IP address or per-domain basis within the Forefront Online Protection for Exchange (FOPE) Administration Center.
See the TechNet article Regulated Partner with Forced TLS Scenario for details.
Encryption Between Clients and Exchange Online
Client connections to Exchange Online use the following encryption methods to enhance security:
- SSL is used for securing Outlook, Outlook Web App, Exchange ActiveSync, and Exchange Web Services traffic, using TCP port 443.
- SSL is also used for POP3 and IMAP, using TCP port 995.
Exchange Online will transport and store Secure/Multipurpose Internet Mail Extensions (S/MIME) messages. However, Exchange Online does not host S/MIME functions, nor does it provide key repository, key management, or key directory services.
To use S/MIME, users must store in their Outlook contacts the public key for every recipient to whom they send encrypted messages. Outlook cannot use the S/MIME certificates stored for users in on-premises Active Directory because the Directory Synchronization tool does not synchronize the Active Directory userSMIMECert attribute to Exchange Online.
S/MIME is supported in Outlook but not in Outlook Web App. Customers are responsible for all PKI infrastructure and user S/MIME certificate enrollment.
Exchange Online will transport and store messages that are encrypted using client-side, third-party encryption solutions such as PGP. Exchange Online does not host the public keys, nor does it provide key repository, key management, or key directory services.
Information Rights Management
Exchange Online does not provide hosted Information Rights Management (IRM) services, but administrators can use on-premises Active Directory Rights Management Services in conjunction with Exchange Online. If an Active Directory Rights Management Services server is deployed, Outlook can directly communicate with the Active Directory Rights Management Services server, enabling users to compose and read messages protected by Active Directory Rights Management Services. There is no need for interoperability between the Active Directory Rights Management Services server and Exchange Online in order to use the Active Directory Rights Management Services features of Outlook.
To enable advanced Active Directory Rights Management Services features introduced in Exchange 2010, administrators can import the Trusted Publishing Domain from their Active Directory Rights Management Services server to Exchange Online using Remote PowerShell. After this one-time import, the following features become available:
- Support for IRM in Outlook Web App
- Support for IRM in Exchange ActiveSync
- IRM search
- Transport protection rules
- Protected voicemail
- Journal report decryption
- Outlook Protection Rules
See the help article Set Up and Manage Information Rights Management in Exchange Online for details.
Support for IRM in Outlook Web App
Users can read and create IRM-protected messages natively in Outlook Web App, just like in Outlook. IRM-protected messages in Outlook Web App can be accessed through Internet Explorer, Firefox, Safari, and Chrome (with no plug-in required) and include full-text search, conversation view, and the preview pane.
Support for IRM in Exchange ActiveSync
Users with mobile devices that support the IRM features of the Exchange ActiveSync protocol can open and work with IRM-protected messages with the appropriate rights—without tethering the phone or installing additional IRM software. Administrators can control the use of this feature using Role-Based Access Control (RBAC) and Exchange ActiveSync policies.
IRM-protected messages are indexed and searchable, including headers, subject, body, and attachments. Users can search protected items in Outlook and Outlook Web App and administrators can search protected items by searching multiple mailboxes.
Transport Protection Rules
Administrators can set up transport protection rules that automatically apply Active Directory Rights Management Services protection to email in transit (including Microsoft Office and XPS attachments). This provides persistent protection for the file regardless of where it is sent and prevents forwarding, copying, or printing, depending on the rights policy template applied.
Either senders or administrators can apply Do Not Forward permissions to voicemail messages in order to prevent them from being forwarded to unauthorized persons, regardless of the email client. These permissions can be applied to all voicemail messages in the organization, or just to voicemail messages that have been marked as private by the sender.
Journal Report Decryption
When journaling messages to an external archive, administrators can include a decrypted, clear-text copy of IRM-protected messages in journal reports, including Microsoft Office and XPS attachments. This allows IRM-protected messages to be indexed and searched for legal discovery and regulatory purposes. The original IRM-protected message is also included in the report.
Outlook Protection Rules
Outlook Protection Rules are a new feature in Outlook 2010. They automatically trigger Outlook to apply an Active Directory Rights Management Services template, based on sender or recipient identities, before users can send an email message. Unlike Transport Protection Rules, Outlook Protection Rules can be configured so that users can turn off protection for less sensitive content.
Archiving and Compliance Features
Exchange Online archiving and compliance features are presented in the sections that follow.
Laws or other regulatory requirements may require organizations to add disclaimers to users’ email messages. Exchange Online lets administrators add disclaimers to messages in transit using transport rules. Administrators can create custom disclaimers for different groups in an organization and can control whether the disclaimers are applied to internal messages, outbound messages, or both.
See the help topic Add Disclaimers to Messages for details.
Transport rules are used to inspect emails in transit (including inbound, outbound, and internal messages) and take actions, such as applying a disclaimer, blocking messages, or sending a blind carbon copy to a mailbox for supervisory review. Transport rules use a set of conditions, actions, and exceptions similar to inbox rules. Exchange Online supports the transport rule functionality of Exchange Server 2010 Service Pack 1, including:
- Granular Transport Rule Conditions: Administrators can create transport rules to inspect messages for a variety of email attributes, such as specific senders, recipients, distribution lists, keywords, and regular expressions (for common patterns like those associated with credit card numbers or social security numbers). Administrators can also include users’ Active Directory attributes (for example, department, country, or manager) and distinguish by message types (such as automatic replies, meeting requests, and voicemail messages).
- Ability to Moderate: Administrators can use transport rules to route email messages to a manager or trusted moderator for review. Reviewers can then approve or block the message and, if blocked, provide an explanation to the sender.
- Message Classifications: Administrators can use transport rules to apply metadata to messages, describing the intended use or audience (for example, attorney–client privileges). Users can also apply classifications manually and have transport rules check messages when they enter the transport pipeline. If messages do not meet the conditions of the classification, an action can be applied to modify, protect, or block the messages.
- Attachment Inspection: Administrators can create transport rules based on content in a Microsoft Office attachment. However, file types, such as Adobe .pdf, that require installation of third-party IFilters on the email server cannot be inspected in Exchange Online.
Administrators can manage transport rules using the Exchange Control Panel or Remote PowerShell. Transport rules can act on all email traffic in an organization, including messages sent and received by users with Kiosk subscriptions. Using transport rules to copy messages to an Exchange Online mailbox for the purposes of archiving is not permitted.
See the help topic Organization-Wide Rules for details.
The maximum number of transport rules that can exist in the organization is 100. The maximum size of an individual transport rule is 4,000 characters. The character limit for all regular expressions used in all transport rules is 20,000. The maximum number of recipients added to a message by all transport rules is 100.
See the help topic Message and Recipient Limits for details.
Note This section describes archiving capabilities available for cloud-based mailboxes in Exchange Online. For details about Microsoft Exchange Online Archiving, a hosted archiving solution for on-premises Exchange 2010 mailboxes, refer to the Exchange Online Archiving Service Description.
Exchange Online provides built-in archiving capabilities, including a personal archive that gives users a convenient place to store older emails. A personal archive is a specialized mailbox that appears alongside users’ primary mailbox folders in Outlook or Outlook Web App. Users can access the archive in the same way they access their primary mailboxes. In addition, users can search both their personal archives and primary mailboxes.
Administrators can use the Exchange Control Panel or Remote PowerShell to enable the personal archive feature for specific users. The personal archive is not available to users with Exchange Online Kiosk subscriptions. See the help topic Enable an Archive Mailbox for details.
Note Using journaling, transport rules, or auto-forwarding rules to copy messages to an Exchange Online mailbox for the purposes of archiving is not permitted.
Client Support for the Personal Archive
Outlook 2010 and Outlook Web App provide users with the full features of the personal archive, as well as related features like retention and archive policies.
Outlook 2007 provides basic support for the personal archive, but not all archiving and compliance features are available in Outlook 2007. For example, with Outlook 2007, users cannot apply retention or archive policies to items in their mailboxes. They must rely on administrator-provisioned policies instead. Outlook 2007 users require the Office 2007 Cumulative Update for February 2011 to access the personal archive.
Note The personal archive has specific licensing requirements for Outlook users, which are described at the help topic License requirements for Personal Archive and retention policies.
Size of the Personal Archive
Each personal archive can be used only for storage of one user’s messaging data. An Exchange Online (Plan 1) user receives 25 gigabytes (GB) of total storage, which the user can apportion across the user’s primary mailbox and personal archive. Therefore, the personal archive for an Exchange Online (Plan 1) user cannot exceed 25 GB in size.
An Exchange Online (Plan 2) user receives 25 GB of storage in the primary mailbox, plus unlimited storage in the personal archive. For Exchange Online (Plan 2) users, a default quota of 100 GB is set on the personal archive, which will generally accommodate reasonable use, including the import of one user’s historical email. In the unlikely event that a user reaches this quota, a call to Office 365 support is required. Administrators cannot adjust this quota upward or downward.
Importing Data to the Personal Archive
Users can import data to personal archives in the following four ways:
- Import data from a .pst file using Microsoft Exchange PST Capture.
- Import data from a .pst file using Outlook’s Import and Export wizard.
- Drag email messages from .pst files into the archive.
- Drag email messages from the primary mailbox into the archive.
- Let archive policies automatically move email messages from the primary mailbox, based on the age of the messages.
Administrator-driven import of .pst files, using the new-mailboximportrequest PowerShell commandlet introduced in Exchange Server 2010 Service Pack 1, is not available in Exchange Online.
Microsoft Exchange PST Capture
Microsoft Exchange PST Capture allows administrators to search for PST files on computers in their organizations and then import those files to mailboxes in their organizations. PST Capture works with both on-premises Exchange servers and Exchange Online.
PST Capture is comprised of the following components:
- PST Capture Central Service: At the heart of PST Capture is the PST Capture Central Service, which maintains the list of all PST files found in an administrator’s organization and manages the data as it is moved to the Exchange Servers or Exchange Online.
- PST Capture Agent: Discovery of the PST files is performed by PST Capture agents that are installed on computers in the organization. The agents also send the PST files they find to the host computer when an import operation is started on the PST Capture Console.
- PST Capture Console: The PST Capture Console is the interface the administrator uses to configure PST searches, specify the target mailboxes for PST files, and track the status of PST import operations and reports. The PST Capture Agent then sends status updates from previous actions to the Central Service.
See the TechNet article Microsoft Exchange PST Capture for details.
Administrators can configure Exchange Online to journal copies of emails to any external archive that can receive messages via SMTP. For example, administrators can journal emails to an on-premises archiving solution. The journaling destination cannot be an Exchange Online mailbox. The maximum number of journal rules that can exist in the organization is 10. Administrators can manage journal rules in the Exchange Control Panel or Remote PowerShell and can configure journaling on a per-user and per-distribution list basis, scoping the journaling to internal recipients, external recipients, or both. Journaled messages include not only the original message but also information about the sender, recipients, copies, and blind copies.
See the help topic Journal Rules for details.
Exchange Online offers retention policies to help organizations reduce the liabilities associated with email and other communications. With these policies, administrators can apply retention settings to specific folders in users’ inboxes. Administrators can also give users a menu of retention policies and let them apply the policies to specific items, conversations, or folders using Outlook 2010 or Outlook Web App. In Exchange Online, administrators manage retention policies using Remote PowerShell. As part of the Exchange Online December 2011 Service Update, administrators can also use the mail control settings in Exchange Control Panel to create and manage retention policies.
Exchange Online offers two types of policies: archive policies and delete policies. Both types can be combined on the same item or folder. For example, a user can tag an email message so that it is automatically moved to the personal archive in a specified number of days and deleted after another span of days.
With Outlook 2010 and Outlook Web App, users have the flexibility to apply retention policies to folders, conversations, or individual messages and can also view the applied retention policies and expected deletion dates on messages. Users of other email clients can have emails deleted or archived based on server-side retention policies provisioned by the administrator, but they do not have the same level of visibility and control.
The retention policy capabilities offered in Exchange Online are the same as those offered in Exchange Server 2010 Service Pack 1. Administrators can use Remote PowerShell to migrate retention policies from on-premises Exchange Server 2010 environments to Exchange Online. Managed Folders, an older approach to messaging records management that was introduced in Exchange 2007, are not available in Exchange Online.
See the help topic Set Up and Manage Retention Policies in Exchange Online for details.
Exchange Online provides legal hold capabilities to preserve users’ deleted and edited mailbox items (including email messages, appointments, and tasks) from both their primary mailboxes and personal archives. Administrators can use the Exchange Control Panel or Remote PowerShell to set legal holds on individual mailboxes or across an organization. This feature also includes an option that automatically alerts them through Outlook 2010 that a hold has been placed on their mailboxes.
See the help topic Put a Mailbox on Litigation Hold for details.
Rolling Legal Hold
Some organizations want to preserve users’ mailbox contents for archiving and eDiscovery purposes, but only for a specific amount of time, such as one year.
As part of the most recent service update, most administrators can now configure rolling legal hold on any Exchange Online (Plan 2) mailbox through Remote PowerShell (LitigationHoldDuration). This way, organizations can ensure that mailbox items are preserved for a specified amount of time. Some customers have not yet received this update and will need to continue contacting Office 365 support to configure rolling legal hold.
See the help topic Put a Mailbox on Litigation Hold for details.
Exchange Online provides a web-based interface for searching the contents of mailboxes in an organization. Through the Exchange Control Panel, administrators can search a variety of mailbox items—including email messages, attachments, calendar appointments, tasks, and contacts. Multi-mailbox search can search simultaneously across primary mailboxes and personal archives. Rich filtering capabilities include sender, receiver, message type, sent/receive date, and carbon copy/blind carbon copy, along with Advanced Query Syntax.
See the help topic Create a New Multi-Mailbox Search for details on how to run multi-mailbox searches.
The Exchange Control Panel and Remote PowerShell can be used to perform searches on mailboxes. See the help topics New-MailboxSearch and Search-Mailbox for details about searching large numbers of mailboxes via PowerShell.
Note The Exchange Control Panel limit can be increased up to 5000 by contacting Microsoft Support. The PowerShell commandlet “Search-Mailbox” does not have a limit on mailboxes to search
Results of multi-mailbox searches are stored in a special type of mailbox, called a discovery mailbox. A discovery mailbox has a 50 GB quota so it can store large numbers of search results. Administrators can connect Outlook to a discovery mailbox, and export the search results to a .pst file. In Exchange Online, administrators cannot directly export mailbox search results to a .pst file.
By default, one discovery mailbox is created for each organization, but administrators can create additional ones via remote PowerShell. Discovery mailboxes cannot be used for any purpose other than storing mailbox search results. See the help topic Create a Discovery Mailbox to Store Search Results for details about discovery mailboxes.
Administrators can also search for and delete inappropriate email messages sent to multiple mailboxes across their organizations. For example, if confidential salary information was accidentally emailed to all employees, an administrator could delete the email from users’ mailboxes. This type of search is not available in the Exchange Control Panel. It must be performed using Remote PowerShell.
See the help topic Search For and Delete Messages from Users’ Mailboxes for details on how to delete messages from users’ mailboxes.
Administrators can preview the results of the search in the Exchange Control Panel when a mailbox search is complete instead of opening the discovery mailbox to view the results. This allows administrators to quickly determine whether the search results are relevant, revise the search query to narrow the search results, and rerun the search. Items in the preview page are read-only versions of the actual search results. After the search has been optimized, the administrator can then copy the results to the discovery mailbox.
See the help topic Preview Multi-Mailbox Search Results for details.
Exchange Online administration features are presented in the sections that follow.
Microsoft Online Services Portal
The Microsoft Online Services Portal allows administrators to add users and user domains, manage licenses, create groups, and perform other administration tasks common across the services in Office 365. From within the console, administrators can follow links to the Exchange Control Panel, where they can manage settings specific to Exchange Online.
Exchange Control Panel
The Exchange Control Panel allows administrators to configure and manage the Exchange Online environment from a web browser. Administrators can access the Exchange Control Panel by choosing one of the following options:
- Clicking a link in the Microsoft Online Services Portal.
- Opening the Outlook Web App Options page and selecting “My Organization.”
The Exchange Control Panel provides several management capabilities, which are organized into four high-level categories:
- Users and Groups: Mailboxes, distribution groups, external contacts, and email migration
- Roles: Administrator roles, user roles, and auditing
- Mail Control: Rules, journaling, e-discovery, and delivery reports
- Phone and Voice: Unified messaging dialing plans, unified messaging gateways, Exchange ActiveSync access, and Exchange ActiveSync device policy
Administrators can give users access to selected features in the Exchange Control Panel, using the Role-Based Access Control framework described later in this document.
Forefront Online Protection for Exchange Administration Center
The Microsoft Forefront® Online Protection for Exchange (FOPE) Administration Center allows Exchange Online customers to manage advanced settings relating to email flow and email hygiene. Within the FOPE Administration center, administrators can:
- Access reports and statistics on e-mail hygiene for their domains
- Set advanced policy filters that are not available via Exchange Online transport rules, such as rules that are triggered by the IP address of inbound or outbound servers
- Configure forced TLS connections for their domains
- Perform advanced message tracing
- Configure organization-level safe and blocked senders
Note: Some settings are read-only in the FOPE Administration Center to help prevent administrators from inadvertently causing problems with their organizations’ mail flow.
Using Remote PowerShell, administrators can connect to Exchange Online to perform management tasks that are not available or practical in the web management interface. For example, they can use Remote PowerShell to automate repetitive tasks, extract data for custom reports, customize policies, and connect Exchange Online to existing infrastructure and processes.
To use Remote PowerShell, administrators’ computers must be running the Windows Management Framework, which contains Windows PowerShell v2 and WinRM 2.0. These components are already installed in computers running Windows 7 or Windows Server 2008 R2. Administrators can manually download these components for computers running other operating systems. Administrators do not need to install any Exchange Server management or migration tools in order to use Remote PowerShell. See the help topic Use Windows PowerShell in Exchange Online for instructions on how to use Remote PowerShell.
Exchange Online uses the same PowerShell commandlets as Exchange Server 2010 Service Pack 1, with certain commands and parameters disabled because these features do not apply in the hosted environment. For a list of the commandlets available to Exchange Online administrators, see Reference to Available PowerShell Cmdlets.
Role-Based Access Control
Exchange Online uses a Role-Based Access Control (RBAC) model that allows organizations to finely control what users and administrators can do in the service. Using RBAC, administrators can delegate tasks to employees in the IT department as well as to non-IT employees. For example, if a compliance officer is responsible for mailbox search requests, the administrator can delegate this administrative feature to the officer.
Exchange Online uses the same RBAC framework as Exchange Server 2010 Service Pack 1. Administrators can use the Exchange Control Panel to assign users to built-in roles and role groups. Alternatively, they can use Remote PowerShell to create custom RBAC roles. For example, an administrator can create a custom role to let the help desk team manage mailboxes only for users in a certain subsidiary or geographic region.
The following role groups are available by default in Exchange Online:
- Organization Management
- View-Only Organization Management
- Recipient Management
- Unified Messaging Management
- Help Desk
- Records Management
- Discovery Management
The Microsoft Online platform has an implementation of role-based permissions that is separate from Exchange Online RBAC. Users who are Global Administrators or Service Administrators in Microsoft Online are automatically assigned to the Organization Management role group in Exchange Online. Users who are Help Desk Administrators in Microsoft Online are automatically assigned to the Help Desk role group in Exchange Online. Otherwise, the two security models are managed separately.
By default, users in the Organization Management role group cannot log in to other user’s mailboxes, and cannot search the content of other user’s mailboxes using multi-mailbox search. However, they can assign themselves these permissions via RBAC. Organizations who want to prevent their administrators from reading other users’ mail can assign these administrators other Role Groups that do not have the ability to modify RBAC permissions. Organizations can also use auditing reports to monitor changes that administrators make to Role Groups and RBAC permissions.
To learn more about configuring RBAC in Exchange Online, see the help topic Role Based Access Control in Exchange Online.
Administrators can use delivery reports to view detailed reporting on email messages within the Exchange Online environment. Using the Exchange Control Panel, they can search for messages and view information such as time and date of delivery, reasons for non-delivery, and policies applied. Users can also view delivery report information for the emails they have sent by accessing the Outlook Web App Options page.
See the help topic Track Messages with Delivery Reports for details.
To access delivery information for messages sent to external destinations, administrators can use the message tracking capabilities within the Forefront Online Protection for Exchange (FOPE) Administration Center.
Administrators can use Remote PowerShell to retrieve information about how people in their organizations use the Exchange Online service. Available information includes:
- Showing the mailbox size for each user in the organization.
- Displaying custom permissions that are set on mailboxes, such as delegate access.
- Extracting data about mobile device access, such as which users are connecting through Exchange ActiveSync, what devices they are using, and when they last connected.
Remote PowerShell commandlets that start with “get-” have the ability to fetch data from the Exchange Online system. Administrators can export this information from PowerShell in .csv format for advanced analysis or reporting.
Exchange Online provides two types of built-in auditing capabilities:
- Administrator Audit Logging: Allows customers to track changes made by their administrators in the Exchange Online environment, including changes to RBAC roles or Exchange policies and settings.
- Mailbox Audit Logging: Allows customers to track access to mailboxes by users other than the mailbox owner, including access by delegates and access to shared mailboxes.
Several predefined audit reports are available in the Exchange Control Panel, including Administrator Role Changes, Litigation Hold, and Non-Owner Mailbox Access. Administrators can filter reports by date and role, and can export all audit events for specified mailboxes in XML format for long-term retention or custom reporting.
Administrator audit logging is on by default, and log entries are retained for 90 days.
Mailbox audit logging is off by default. Administrators can use Remote PowerShell to enable mailbox audit logging for some or all mailboxes in their organization. When mailbox audit logging is enabled, log entries are retained for 90 days by default. This value can be raised or lowered using Remote PowerShell (Set-Mailbox <Identity> -AuditLogAgeLimit).
See the help topic Use Auditing Reports in Exchange Online for details.
Application Interoperability Features
Administrators can connect many kinds of on-premises and hosted applications to Exchange Online, including custom line-of-business applications and software from third-party vendors.
- The application vendor must provide support for the application and perform all related application compatibility testing.
- Custom applications cannot be hosted in a Microsoft data center, unless they are hosted on the Windows Azure™ platform.
- Exchange Online does not host custom code or third-party applications, including .dlls, custom code packaged in transport agents, or allow modifications to files on servers in the data center.
- Applications that send email messages are subject to the same recipient limits and message rate limits as regular mailboxes. These limits are described in the Recipient Limits section of this document.
The following sections describe the methods available for connecting applications to Exchange Online and identify some Exchange Server application programming interfaces (APIs) that are unavailable in Exchange Online.
Exchange Web Services
Exchange Web Services (EWS) is the preferred development API for Exchange Server and Exchange Online. Using EWS or the EWS Managed API, administrators can access data stored with Exchange Online from applications that are running on-premises, in Windows Azure, or in other hosted services. EWS can perform specialized actions, such as querying the contents of a mailbox, posting a calendar event, creating a task, or triggering a specific action based on the content of an email message.
For details on how to use Exchange Web Services with Exchange Online, refer to the technical articles at the Exchange Online Developer Center.
Exchange Online can be used as an SMTP delivery service to relay email messages sent from fax gateways, network appliances, and custom applications. For example, if a line-of-business application sends email alerts to users, it can be configured to use Exchange Online as the mail delivery system. The application or service must authenticate with the username and password of a valid, licensed Exchange Online mailbox, and connect using TLS. The SMTP server name to use can be found by logging into Outlook Web App, viewing the Options page, and clicking “Settings for POP, IMAP, and SMTP access.” Applications that use SMTP relay are subject to the same recipient limits and message rate limits as regular users. These limits are described in the Recipient Limits section of this document.
Outlook Web App Web Parts
Exchange Online supports Outlook Web App Web Parts via manually configured URLs. Built-in SharePoint OWA Web Part controls will not work against Exchange Online.
Outlook Add-Ins and Outlook MAPI
Most Outlook add-ins will work with Exchange Online. Microsoft does not provide support or troubleshooting help for Outlook add-ins. Customers must contact the vendor that created the add-in for assistance.
Custom applications that use the Outlook MAPI library typically can connect to Exchange Online, but those that use the Exchange Server MAPI library will not connect (see the next section for details). If a custom application requires Outlook to be installed in order to function, it probably uses the Outlook MAPI library.
Exchange Server MAPI/CDO
Some third-party applications use Exchange Server MAPI Client and Collaboration Data Objects (MAPI/CDO) for server-to-server communication with Exchange. These applications need to be installed within the same local network as Exchange and will not connect over the Internet to Exchange Online.
The Exchange WebDAV API was removed from Exchange Server 2010 and is not available in Exchange Online.
Lync Server 2010 or Office Communications Server 2007 R2
For customers who have deployed Microsoft Lync Server 2010 on premises, Microsoft Office Communicator can connect to Exchange Online using Exchange Web Services to access out-of-office messages and calendar data.
On-premises Lync Server 2010 can interoperate with Exchange Online in two additional ways:
- IM and presence interoperability in Outlook Web App (see the Office Web App section of this document for details)
- Voicemail interoperability (see the TechNet article Providing Lync Server 2010 Users Voice Mail on Hosted Exchange UM for details)
The TechNet blog Configuring On-Premises Lync Server 2010 Integration with Exchange Online contains additional details on how to configure Lync Server to interoperate with Exchange Online.
For customers who have deployed Microsoft Office Communications Server 2007 R2 on premises, Microsoft Office Communicator can connect to Exchange Online using Exchange Web Services; however, multiple authentication prompts may be required.
Public folders are not available in Exchange Online. To learn about strategies for transitioning away from public folders as part of a migration to Exchange Online, see the Migrate from Exchange Public Folders to BPOS whitepaper:
To simplify management of the Microsoft Office 365 environment, Microsoft provides the Microsoft Online Services Directory Synchronization tool to help synchronize a company’s local Active Directory data with Exchange Online, SharePoint Online, and Lync Online. The tool is available free of charge.
Administrators can download the Directory Synchronization tool from the Administration Center and install it on a computer in the on-premises network where Active Directory resides. The Directory Synchronization tool creates an account in Exchange Online for all mail-enabled users in the Active Directory forest as well as for distribution groups, and global contacts. Subsequent updates to user accounts—such as adding, deleting, or modifying user accounts—are pushed by the Directory Synchronization tool to Exchange Online.
The Directory Synchronization tool plays an important role in hybrid email scenarios, enabling smooth migration from on-premises Exchange Server to Exchange Online. After the migration is complete, the Directory Synchronization tool helps simplify management of the Exchange Online environment by eliminating the need to manage Active Directory users and groups in two places.
Note The Directory Synchronization tool supports synchronization from only one customer Active Directory forest to Microsoft Office 365.
The Directory Synchronization tool performs a one-way synchronization from on-premises Active Directory to Exchange Online. Changes made in Exchange Online are not synchronized to the on-premises Active Directory, and no on-premises Active Directory objects are updated by Directory Synchronization tool, unless the administrator enables an optional feature called Directory Sync Writeback.
Directory Sync Writeback makes it easier for organizations that configure a hybrid deployment between Exchange Server 2010 and Exchange Online to move cloud mailboxes back on-premises (see the Migration and Hybrid Deployments section). When users are moved back on-premises, Directory Sync Writeback automatically updates selected Active Directory properties to preserve their ability to reply to historical messages in their mailboxes. It also brings users’ safe and blocked sender lists back to the on-premises environment.
Directory Sync Writeback is required for organizations that deploy Exchange Online Archiving, a cloud-based email archive for users with on-premises Exchange Server 2010 mailboxes. See the Exchange Online Archiving Service Description for details.
Migration and Hybrid Deployments
Microsoft provides tools to help migrate an existing email environment to Exchange Online. Using these tools, administrators can migrate to Exchange Online from:
- IMAP-based email systems
- Microsoft Exchange Server 2003
- Microsoft Exchange Server 2007
- Microsoft Exchange Server 2010
Tools for migrating from other email systems, such as IBM Lotus Notes/Domino and Novell GroupWise, will be provided by third-party vendors.
Organizations should choose migration options based on their source email systems, desired end state (fully hosted or partially hosted), the number of users to migrate, and how quickly the end state needs to be reached. At a high level, organizations have the following options:
- IMAP migration: Migrate data from IMAP-based email systems to Exchange Online with a single cutover migration.
- Cutover Exchange migration: Migrate data from Exchange 2003, Exchange 2007, Exchange 2010, and Hosted Exchange systems to Exchange Online in a single cutover migration.
- Staged Exchange migration: Perform a staged migration from Exchange 2003 or Exchange 2007 with web-based migration tools and minimal changes to on-premises infrastructure.
- Exchange hybrid deployment: Add an Exchange 2010 Service Pack 1 server to the on-premises Exchange 2003 or Exchange 2007 environment and use the Exchange Management Console to move mailboxes to Exchange Online.
For more details on migration and hybrid deployment options, see the help topic Choose a migration or coexistence option.
Email Migration Dashboard
Administrators can use the Email Migration dashboard in the Exchange Control Panel to manage mailbox migration to Exchange Online using a cutover or staged Exchange migration. Administrators can also use the dashboard to migrate the contents of users’ mailboxes from an on-premises IMAP server to existing cloud-based mailboxes. The dashboard gives administrators the following capabilities:
- Create and schedule multiple migration batches: Administrators can create and queue up to 100 migration batches for a staged Exchange migration or an IMAP migration. Only one migration batch runs at a time, but administrators can queue up multiple batches, so when a migration batch is finished running the next batch in the queue starts.
- Restart a migration batch with failures: After the initial synchronization for a migration batch, where items are copied from on-premises mailboxes to the cloud mailboxes for each user in the migration batch, some mailboxes may fail synchronization. Now administrators can restart that migration batch and try to synchronize the failed mailboxes.
- Get details about skipped items: For cutover Exchange migrations and staged Exchange migrations, the migration dashboard now displays information about the specific items that were skipped, including the reason why the items skipped and the location of the item in the user’s mailbox.
- Open migration reports: Administrators can open migration statistics or migration error report for a migration batch right from the dashboard.
- Edit a migration batch: If a migration batch for a staged Exchange migration or an IMAP migration is in the migration queue (but isn’t currently running), administrators can edit the migration batch by submitting a new CSV file, changing the connection settings, or changing the number of mailboxes to migrate simultaneously.
See the help topic Manage Migration Batches in Exchange Online for details.
Troubleshooting Migration Errors
Improved diagnostic capabilities help administrators troubleshoot migration errors. For example, Remote PowerShell can be used to display diagnostic information for a migration batch named MigrationBatch1 (Get–MigrationBatch –Identity MigrationBatch1 –Diagnostic), as well as display migration statistics and diagnostic information for a user with a primary SMTP address of email@example.com (Get–MigrationUserStatistics –Identity firstname.lastname@example.org –Diagnostic).
See the help topic Email Migration Users Status Report for details.
Exchange Online offers a web-based tool for migrating data from email systems that support IMAP. It guides administrators through the following migration steps:
- Create empty mailboxes in the cloud for users in the organization (typically this is done by uploading a .csv file or using Remote PowerShell).
- Enter the remote server connection settings.
- Specify a list of mailboxes to be moved.
- After this information is entered, Exchange Online begins to migrate email content via IMAP (calendar items, contacts, tasks, and other non-mail items are not migrated).
During the migration, to avoid overusing the remote server’s resources and bandwidth, Exchange Online creates fewer than 10 connections to the IMAP server.
See the help topic Migrate E-Mail from an IMAP Server to Cloud-based Mailboxes for details about IMAP Migration.
Cutover Exchange Migration
Exchange Online offers a web-based tool for migrating data from on-premises Exchange Server 2003, Exchange Server 2007, or Exchange Server 2010 environments. It guides an administrator through the following migration steps:
- Enter the address of the remote Exchange Server and credentials for an on-premises administrator account.
- Exchange Online uses an RPC/HTTP connection to read directory information from the remote server and create mailboxes in Exchange Online.
- Exchange Online synchronizes the mailbox content to the cloud mailboxes. Users remain connected to their original mailboxes while their data is being migrated to Exchange Online.
- After the initial migration is complete, any changes are synchronized to the cloud every 24 hours until the administrator finalizes the migration.
To switch users to their cloud mailboxes, administrators reconfigure the users’ profiles in Outlook. When users switch to their cloud mailboxes, their local offline folders (.ost files) will resynchronize, resulting in the download of migrated mail to the client workstation. Users can reply to old messages in their mailboxes after migration.
For this migration method, Exchange Online needs to connect to an on-premises Exchange Server, so the on-premises server must have a certificate issued by a trusted certificate authority and public IP address. Administrators cannot use this migration method to migrate more than 1,000 users.
See the help topic Migrate All Mailboxes to the Cloud with a Simple Exchange Migration for details about Exchange cutover migration.
Staged Exchange Migration
With a staged migration, users can be migrated to the cloud using the web-based Exchange migration tool described earlier in this document. The same conditions and limitations of regular Exchange migration apply. However, instead of migrating all users at once, administrators migrate users in stages. This is accomplished by uploading a .csv file to specify a partial list of users to migrate.
Staged Exchange migration requires administrators to use the Directory Synchronization tool. This provides users with a unified Global Address List where the online environment is continuously synchronized with the on-premises environment. In a staged migration, all of the users in an organization can share the same email domain name, but on-premises users cannot see calendar or free/busy information for Exchange Online users, and vice versa.
See the help topic Migrate a Subset of Mailboxes to the Cloud with a Staged Exchange Migration for details.
Exchange Hybrid Deployment
Organizations running Exchange Server 2003, Exchange Server 2007, or Exchange Server 2010 can establish a hybrid deployment between Exchange Server and Exchange Online. Hybrid deployments enable a smooth migration experience and allow organizations to keep a mix of on-premises users and online users for an extended period of time. Hybrid deployments provide these advantages:
- Cloud and on-premises users can share free/busy calendar data. This includes full calendar sharing and free/busy details for users on Exchange Server 2010, full free/busy details for users on Exchange Server 2007, and basic free/busy information for users on Exchange Server 2003.
- Administrators can use the Exchange Management Console to manage cloud and on-premises environments.
- Administrators can use powerful and familiar Exchange management tools to move users to the cloud.
- Administrators do not need to manually reconfigure Outlook profiles or resynchronize .ost files after moving users’ mailboxes.
- MailTips, out-of-office messages, and similar features understand that cloud and on-premises users are part of the same organization.
- Delivery reports and multi-mailbox search work with users who are on-premises and those working in the cloud.
- Authentication headers are preserved during cross-premises mail flow, so all mail looks and feels like it is internal to the company (for example, recipient names resolve in the Global Address List). This feature requires a direct SMTP connection between Exchange Online and on-premises Exchange Server 2010 SP1 Edge servers or Hub Transport servers (email must not be routed through any other SMTP gateway).
- If necessary, administrators can easily move mailboxes back to the on-premises Exchange environment.
To implement a hybrid deployment, administrators deploy an Exchange Server 2010 Service Pack 1 server in their Exchange Server 2003 or Exchange Server 2007 environments and configure Exchange federation with Exchange Online. The Exchange 2010 server acts as a bridge between Exchange 2003 or Exchange 2007 environments and Exchange Online. Organizations do not need to upgrade mailboxes to Exchange 2010 prior to moving them to the cloud.
Note Organizations that install an Exchange 2010 server solely to act as a bridge between their Exchange Server 2003 or Exchange Server 2007 on-premises environments and Exchange Online can request a Hybrid Edition server key to license the server. See the Exchange Online Licensing page for details.
Hybrid deployments require the Directory Synchronization tool to be running in the local environment. Directory Sync Writeback is recommended to enable smooth offboarding of users (see the Directory Synchronization section of this document for details). Deployment of Active Directory Federation Services 2.0 is also recommended to enable single sign-on.
See the help topic Exchange Online Hybrid Deployment and Migration with Office 365 for details about Exchange hybrid deployments.
Hybrid Configuration Wizard
The Hybrid Configuration Wizard can help to streamline the hybrid deployment process by simplifying configuration of features and services. Introduced as part of Exchange Server 2010 Service Pack 2, the Hybrid Configuration Wizard consists of the following components:
- A new Exchange Management Console (EMC) wizard that guides administrators through the end-to-end process for configuring a hybrid deployment.
- A set of Exchange Management Shell (EMS) commands that orchestrate the configuration process.
- Improvements to the manageability of some of the underlying hybrid features.
See the TechNet article Hybrid Deployments with the Hybrid Configuration Wizard for details.
Exporting Data from Exchange Online
To export data from Exchange Online, an administrator can connect Outlook to Exchange Online mailboxes, and then export the data to PST files. See the help topic Export Mailbox Data From Exchange Online for details.
Organizations that have configured an Exchange hybrid deployment also have the option of off-boarding mailboxes to on-premises Exchange Server 2003, 2007, or 2010. See the wiki topic Exchange Hybrid Deployment – Moving Cloud-Based Mailboxes to the On-Premises Organization for details.
Appendix A: Exchange Online and Exchange Server Feature Comparison
Exchange Server 2010 Exchange Online SERVICE FEATURES Mailbox size Configurable 1 GB for Exchange Online Kiosk user, 25 GB for Exchange Online (Plan 1) user, unlimited for Exchange Online (Plan 2) user Message size limits (max attachment size) Configurable 25 MB Recipient limits Configurable 1,500 recipients/day Message rate limits Configurable 30 messages/minute Deleted item recovery Configurable 14 Days Deleted mailbox recovery Configurable 30 Days CLIENT ACCESS Outlook 2010 Yes Yes Outlook 2007 Yes Yes Outlook 2003 Yes Yes (POP or IMAP only) Outlook Anywhere (RPC over HTTPS) Yes Yes Outlook Cached Mode Yes Yes Outlook Online Mode Yes Yes (not recommended) Autodiscover Yes (for Outlook and mobile) Yes (for Outlook and mobile) Outlook Web App Internet Explorer 7+, Safari 3+, Firefox, Chrome Internet Explorer 7+, Safari 3+, Firefox, Chrome Outlook Web App light experience Almost any browser Almost any browser Outlook Web App: Vanity URL (http://mail.contoso.com) Yes Customer can set up a redirect Public/private computer logon option Yes No Outlook Web App: session time-out Configurable Default: 6 hours
Configurable up to 24 hours.
WebReady document viewing Yes Yes Disable web access Yes Yes Instant messaging and presence connected to web email client Yes Yes Macintosh support (rich client) Outlook for Mac 2011, Entourage 2008 Web Services Edition Outlook for Mac 2011,
Entourage 2008 Web Services Edition
IMAP Yes Yes POP Yes Yes MOBILITY Windows Phone 7 devices Yes Yes Windows Mobile devices Windows Mobile 5.0+ Windows Mobile 6.0+ Other Exchange ActiveSync devices (such as iPhone) Yes Yes Remote device wipe (implementation varies by mobile device manufacturer) Yes Yes Customize Exchange ActiveSync security policies and settings, including PIN/password lock Yes Yes Disable Exchange ActiveSync access Yes Yes Mobile device allow/block/quarantine Yes Yes Certificate-based authentication for Exchange ActiveSync Yes No Over-the-air-update for Outlook Mobile Yes Yes Mobile SMS sync (through Exchange ActiveSync) Yes Yes SMS (text messaging) notifications Yes Yes BlackBerry (via Blackberry Enterprise Server) Yes Yes – via BlackBerry Business Cloud Services BlackBerry (via Blackberry Internet Service) Yes Yes EMAIL/INBOX “Send on behalf of” and “send as” Yes Yes Shared mailboxes Yes Yes Catch-all mailbox Yes No Server-side email forwarding Yes Yes Inbox rules Yes Yes Tasks Yes Yes Conversation view and actions (such as ignore conversation) Yes Yes MailTips and MailTips customization Yes Yes Connected accounts (aggregate mail from multiple external email accounts) No Yes CONTACTS/DIRECTORY Personal contacts Yes Yes Personal distribution groups Yes Yes Shared distribution groups
(in Global Address List)
Yes Yes—managed via web or synchronized from Active Directory Restricted distribution groups Yes Yes Dynamic distribution groups Yes Yes Moderated distribution groups Yes Yes Self-service distribution groups Yes Yes (for groups not synchronized from on-premises Active Directory) Global Address List Yes Yes Hide users from Global Address List Yes Yes Custom address lists Yes No Hierarchical address lists Yes No Address Book Policies Yes No Offline Address Book Yes Yes External contacts (in Global Address List) Yes Yes CALENDAR Out-of-office auto-replies Yes Yes Cross-premises calendar free/busy (mix of on-premises/cloud users) Not applicable Yes Federated calendar sharing Yes Yes Publish or subscribe to calendar through iCal Yes Yes Side-by-side calendar view in web client Yes Yes Resource mailboxes (for example, for conference rooms or equipment) Yes Yes Outlook 2010 Room Finder Yes Yes UNIFIED MESSAGING, FAX Interoperability with on-premises voicemail systems Yes Via SMTP or Exchange Web Services Exchange Unified Messaging (hosted voicemail) Yes Yes SECURITY Anti-spam (AS) Customer chooses AV/AS solution Forefront Online Protection for Exchange Antivirus (AV) Customer chooses AV/AS solution Forefront Protection for Exchange Safe and blocked senders (configurable at the organization level) Yes Yes Opportunistic TLS for inbound/outbound email Yes Yes Forced TLS for inbound/outbound email Yes Yes S/MIME Yes Yes, with limitationsNo Outlook Web App support PGP Yes Yes COMPLIANCE/ARCHIVING Disclaimers Yes Yes Transport rules Yes Yes Personal archive Yes Yes Retention policies Yes Yes: Exchange 2010 retention policies
No: Exchange 2007-style managed folders
Journal messages to external or on-premises archive Yes Yes Multi-mailbox search (eDiscovery) Yes Yes Legal hold Yes Yes Rolling legal hold Yes Yes ADMINISTRATION Administration through a Web-based interface (Exchange Control Panel) Yes Yes Forefront Online Protection for Exchange Administration Center access Optional Yes Administration through command line shell (PowerShell) Yes Yes Role-Based Access Controls (RBAC) Yes Yes Message tracking Yes Yes Usage reporting Some data can be extracted using PowerShell Some data can be extracted using PowerShell Auditing Yes Yes APPLICATION ACCESS/CUSTOMIZATION Application connectivity through web services Yes Yes SMTP relay Yes Yes Outlook Web App Web Parts Yes Yes Outlook add-ins and Outlook MAPI Yes Yes Application connectivity through Exchange Server MAPI/CDO API Yes No Application connectivity through DAV No No OTHER Public folders Yes No Global Address List synchronization from on-premises directory (Active Directory) Not applicable Yes—one-way through the Directory Synchronization tool Global Address List synchronization from multiple on-premises Active Directory forests Yes No