Planning overview for Outlook 2010


Applies to: Office 2010

Topic Last Modified: 2012-03-21

Banner stating end of support date for Office 2010 with link to more info

A close review of your organization's messaging requirements will help you plan an optimal Microsoft Outlook 2010 deployment. This article guides you through the things to consider when you deploy Outlook 2010.

In this article:

  • Determining an organization’s needs

  • Choosing when and how to install Outlook

  • Security and privacy considerations

  • Upgrading from an earlier version of Outlook

  • Additional considerations when planning an upgrade

  • Upgrading from other mail and scheduling programs

Determining an organization’s needs

The organization's messaging environment helps shape the Outlook 2010 deployment. Factors to consider include whether you are upgrading Outlook, installing the application for the first time, planning for roaming or remote users, or choosing a combination of these and other factors.

Upgrade or initial installation

If you are upgrading to Outlook 2010 from an earlier version of Microsoft Outlook, consider whether you will migrate previous settings, modify user profiles, and use new customization options. The Office Customization Tool (OCT) enables you to migrate users' current settings and make other customizations, such as define new Microsoft Exchange servers (including Exchange Online) or customize new features. User settings are migrated automatically by default, except for security settings.

If you are deploying Outlook on client computers for the first time, each user needs an Outlook profile to store information about e-mail messaging server connections and other important Outlook settings. You can use the OCT or deploy an Outlook Profile (.prf) file to define profile settings for users.

For more information, see the following articles.

Migrating data

If the organization uses a different mail client, you might have to migrate data from those clients to Outlook 2010. The importers that are provided in Outlook (for example, for Eudora Light) might be helpful. Importers cannot be configured to run automatically. Use importers to migrate data for individual users.

Remote and roaming users

You can customize Outlook to optimize the experience for remote and roaming users, and to set up Outlook for multiple users on the same computer.

You might want to configure features such as Outlook Anywhere (known as RPC over HTTP in earlier versions of Outlook) and Cached Exchange Mode for remote users. These features enhance the user experience when Outlook is used over slower or less reliable connections. By using Outlook Anywhere, you can configure connections that enable users to connect more securely from the Internet to Exchange servers in your organization or to Exchange Online without using a virtual private network (VPN) connection. Cached Exchange Mode is an Outlook feature that was introduced with Office Outlook 2003. It creates a local copy of users' mailboxes. Cached Exchange Mode is recommended for all configurations, but especially benefits remote users. The feature enables users to have more reliable access to their Outlook data, whether or not they are connected to a network. For more information, see Configure Outlook Anywhere in Outlook 2010 and Plan an Exchange deployment in Outlook 2010.

When multiple users share the same computer, use Windows logon features on the computer's operating system to manage user logon verification. Unless you deploy application virtualization, users must use the same version of Outlook because only one version of Outlook can be installed on the same computer. To learn more about how to set up multiple Outlook users on the same computer, see Using Outlook on a computer you share with other people (

Multilingual requirements

Microsoft Office 2010 provides broad support for deployment in international or multilingual environments. As with the 2007 Microsoft Office system, the Office 2010 product consists of the language-neutral core package plus one or more language-specific packages. In addition to the proofing tools that are included in each language version, you can download and deploy proofing tools for other languages to help multilingual groups work with and edit files in many languages. For more information, see Plan for multilanguage and Proofing Tools deployment for Office 2010.

Outlook 2010 supports Unicode throughout the product to help multilingual organizations seamlessly exchange messages and other information in a multilingual environment.

Client and messaging server platforms

Some features of Outlook 2010 (for example, Cached Exchange Mode) require Microsoft Exchange Server as a messaging platform. Although Outlook 2010 works well with earlier versions of Exchange, some features of Outlook 2010 require specific versions of Exchange. Because of this and other improved integration with Exchange throughout Outlook 2010, we recommend that you combine Outlook 2010 with the latest version of Exchange Server or use Exchange Online. For more information, see Assess how Outlook 2010 works with different versions of Exchange Server.

Deployment customization decisions for Outlook 2010 depend on which version of Exchange Server you use. If you currently use Exchange Server as your messaging server and you have not upgraded to Exchange 2003 or a later version, consider coordinating the Exchange Server upgrade or Exchange Online migration with the deployment timing for Outlook 2010. Exchange Server 2003 is the earliest version of Exchange Server that can be used with Outlook 2010.

If you have an on-premise Exchange Server and plan to add Exchange Online to co-exist in your environment, there are two things to consider:

  • There is no cross-premises manager delegation. If the manager’s account is on Exchange Online, the delegate’s account must be on Exchange Online too.

  • An account that is on-premise cannot have “Send As” permissions for an account that is on Exchange Online.

Also be aware that the user authentication method is different between an on-premise Exchange Server and Exchange Online. An Exchange Online user enters his or her email address (as the user name) and password. However, the user can decide to save the password so the user only has to enter it one time.

Choosing when and how to install Outlook

You have options for when and how you install Outlook 2010. For example, consider whether which of the following would be best for your organization:

  • Install or upgrade Outlook for different groups of users in stages, or at the same time.

  • Install Outlook as a stand-alone application.

  • Install Outlook before, during, or after Office 2010 installation.

Each organization has a different environment and might make a different choice about timing Outlook 2010 upgrades. For example, you might have a messaging group that is responsible for upgrading Outlook and a separate group that plans deployment for other Microsoft Office applications. In this case, it might be easier to upgrade Outlook separately from the rest of Office, instead of attempting to coordinate deployment between the two groups.

Note that Outlook 2010 cannot coexist with previous versions of Outlook on the same computer. If you have to use previous versions, do not install Outlook 2010 or deploy Outlook 2010 with application virtualization. For more information, see Determine when to install Outlook 2010.

Customizing Outlook settings and profiles

You can customize an Outlook installation to handle Outlook user settings and profiles in two ways:

  • Specify Outlook user settings in the OCT.

  • Specify options for managing new and existing Outlook profiles in the OCT or use an Outlook Profile file (.prf).

For example, you can enable Outlook users to migrate their current profiles and settings while default profiles and settings are defined for new Outlook users. You can also modify existing profiles and establish new default profiles for new Outlook users. If you deploy Outlook 2010 with Microsoft Exchange Server 2010 or Exchange Online, you can add more than one Exchange account for a profile by using the OCT or .prf file.

When you use the OCT to customize Outlook, you save choices and other installation preferences in the customization file that is applied during Setup. Later, you update settings and profile information by opening the file in the OCT and saving a new copy of the file.

For more information about how to configure Outlook profiles, see Office Customization Tool in Office 2010 and Customize Outlook profiles by using an Outlook Profile (PRF) file. These articles also apply to environments that have Exchange Online deployed.


There is a known issue in which an additional Exchange account is added to the Outlook profile when a user who already has an exchange account in the profile is upgraded from Outlook 2003 or Outlook 2007. This issue can occur while you are upgrading Outlook and applying customizations by using a custom OCT file (.msp) or .prf file that is configured to “Modify Profile" and "Define changes to make to the existing default profile.”
To prevent multiple Exchange accounts from being created in one profile when you upgrade users to Outlook 2010, you must download and use the Service Pack 1 (SP1) version of the OCT, which is available from the Microsoft Download Center ( To update the OCT, replace the /Admin folder that is in your Office 2010 installation files or installation image with the new /Admin folder that is included in the download package. If you do not use the SP1 version of the OCT, you must create a .prf file and set the properties BackupProfile=False and UniqueService=Yes. For the steps to do this, see Multiple Exchange accounts created in Outlook 2010 with existing Outlook profiles after upgrading from an earlier Office version using a custom MSP (

Configuring subscriptions and other sharing features

As with Office Outlook 2007, Outlook 2010 includes features that let you easily subscribe to new sources of content and share the features with users inside and outside your organization. Content sources include Microsoft SharePoint Foundation 2010 and SharePoint Foundation 2010 contacts, tasks, and calendars, together with local and Internet-based calendars (iCals).

Really Simple Syndication (RSS) is another sharing feature that enables users to subscribe to internal or Internet-based sources of syndicated content (.xml files) to avoid having to check a site for new information. You can deploy specific RSS feeds or calendar subscriptions to users, configure settings to manage how users can share these subscriptions or content, specify how often the servers update users' copies of the data, and more.

Using Outlook with Remote Desktop Services (Terminal Services)

Remote Desktop Services in Windows Server enables you to install a single volume licensed copy of Outlook 2010 on a Remote Desktop Services-enabled computer. Instead of having Outlook run on local computers, multiple users connect to the server and run Outlook from that server.

To achieve optimal results when you use Outlook with Remote Desktop Services, pay attention to how you customize your Outlook configuration. For example, in Outlook 2010 you can configure Cached Exchange Mode with Remote Desktop Services. However, you will have to provide sufficient disk space to accommodate each user’s mailbox on the Remote Desktop Session Host server computer (terminal server). Note that Outlook might be part of an environment that includes other applications that are provided on the same Remote Desktop Session Host computer. For more information, see Cached Exchange Mode in a Remote Desktop Session Host environment: planning considerations (Outlook 2010) (white paper).

Collaboration Data Objects dependencies

Collaboration Data Objects (CDO) is not supported in Outlook 2010. Although some solutions that depend on CDO 1.2.1 might continue to run, CDO 1.2.1 is not designed for a multiple Exchange account environment and unexpected results can occur. For Outlook solutions, use the Outlook object model instead of CDO 1.2.1.


Outlook mailboxes grow as users create and receive items. To keep mailboxes manageable, users need another place to store — or archive — older items that are important but rarely used. It is typically most convenient to automatically move these older items to the archive folder and to discard items whose content has expired and is no longer valid. Outlook 2010 AutoArchive can manage this process automatically for users. However, we recommend that you use the Personal Archive feature in Microsoft Exchange Server 2010 Messaging Records Management (MRM) (or in Exchange Online) because it eliminates the need for Personal Folder files (.pst). By using Personal Archive in Exchange Server 2010 or in Exchange Online, the e-mail archive folders are stored online so that users can access the archived files by using Microsoft Outlook Web App or from a secondary computer by using Outlook 2010. By using either of these client applications, users can view an archive mailbox and move or copy messages between their primary mailboxes and the archive.

Note that when Personal Archive is enabled, AutoArchive is not available to the user and does not archive messages.

If you plan to deploy Outlook 2010 with Exchange Server 2010 or Exchange Online, consider using the Exchange Server Personal Archive feature instead of Outlook 2010 AutoArchive. For more information, see Understanding Personal Archive: Exchange 2010 Help (, Plan for compliance and archiving in Outlook 2010, and Microsoft Exchange Online Archiving(

If you choose to use the AutoArchive feature in Outlook 2010, you can configure the settings to customize Outlook 2010 AutoArchive by using the Outlook Group Policy template (Outlk14.adm). Or you can configure default settings by using the Office Customization Tool (OCT), in which case users can change the settings.

Outlook data files (.pst)

If you plan to deploy Outlook 2010 with Exchange Server 2010 or Exchange Online, we recommend that you use the Personal Archive feature in Exchange Server 2010 Messaging Records Management (MRM) (or in Exchange Online) because it eliminates the need for Outlook data files (.pst). By using the Personal Archive in Exchange Server 2010 or in Exchange Online, the e-mail archive is stored online so that users can access the archived files by using Microsoft Outlook Web App or from a secondary computer by using Outlook 2010. By using either of these client applications, users can view an archive mailbox and move or copy messages between their primary mailboxes and the archive. For more information, see Understanding Personal Archive: Exchange 2010 Help (, Plan for compliance and archiving in Outlook 2010, and Microsoft Exchange Online Archiving (

If you plan to deploy Outlook 2010 with Exchange Server 2003 or Exchange Server 2007, you can configure .pst files to be stored locally (recommended) or on a network share. For more information about the requirements for using .pst files on a network share, see Limits to using personal folders (.pst) files over LAN and WAN links (

Retention policies

Retention policy settings can help users follow retention policy guidelines that your organization establishes for document retention. With Outlook 2010, you cannot deploy AutoArchive-based retention settings through Outlook 2010 by using Group Policy. If you must deploy retention policies, explore the Messaging Records Management (MRM) features in Exchange Server 2010. For more information, see Messaging Records Management: Exchange 2010 Help ( and Plan for compliance and archiving in Outlook 2010.

Security and privacy considerations

Outlook includes many security and privacy features some of which are highlighted in the following sections. For more information about how to plan for security and privacy in Outlook 2010, see Plan for security and protection in Outlook 2010 and Choose security and protection settings for Outlook 2010.

The Trust Center for Office

The Trust Center, introduced with the 2007 Office system, provides a central location for security and privacy options. The Very High, High, Medium, and Low security levels that were used in earlier versions of Office have been replaced with a more streamlined security system.

Limiting viruses and junk e-mail messages for users

Outlook 2010 includes features to help minimize the spread of viruses and to help users avoid junk e-mail.

As in Office Outlook 2007, in Outlook 2010 you can configure virus-prevention and other security settings in Group Policy to support the needs of an organization. You can also use the Outlook Security Template to configure settings, as in earlier releases of Outlook. By using either configuration method, you can, for example, modify the list of file types that are blocked in e-mail messages.

The Object Model (OM) Guard that helps prevent viruses from using the Outlook Address Book (OAB) to spread is updated. Outlook checks for up-to-date antivirus software to help determine when to display OAB access warnings and other Outlook security warnings.

Outlook 2010 has several features to help users reduce receipt of junk e-mail messages. Outlook 2010 includes a Junk E-mail Filter that replaces the rules that were used in previous versions of Outlook to filter mail. Messages caught by the filter are moved to the Junk E-mail folder, where they can be viewed or deleted later. Outlook 2010 includes a Postmarking feature that was introduced with Office Outlook 2007 that can help the Junk E-mail filter determine valid e-mail messages.

Junk e-mail senders can include a Web beacon in HTML e-mail messages that includes external content, such as graphic images. When users open or view the e-mail, the Web beacons verify that their e-mail addresses are valid. This increases the probability that they will receive more junk e-mail messages. Outlook 2010 reduces the probability that users will become targets for future junk e-mail by blocking automatic picture downloads from external servers by default.

Outlook 2010 helps protect against issues created by phishing e-mail messages and deceptive domain names. By default, Outlook screens phishing e-mail messages — e-mail that seems to be legitimate but is designed to capture personal information, such as a user's bank account number and password. Outlook also helps prevent the receipt of e-mail messages from deceptive users by warning about suspicious domain names in e-mail addresses. Outlook 2010 supports internationalized domain names (IDNs) in e-mail addresses. IDNs allow people to register and use domain names in their native languages instead of online English. IDN support allows phishers to send homograph attacks, a situation in which a look-alike domain name is created by using alphabet characters from different languages, not just English, with the intention of deceiving users into thinking that they are visiting a legitimate Web site.

For more information, see Choose security and protection settings for Outlook 2010 and Plan for limiting junk e-mail in Outlook 2010.

Configuring cryptographic features

Outlook provides cryptographic features for sending and receiving security-enhanced e-mail messages over the Internet or local intranet. You can customize features in an Outlook 2010 deployment to set cryptographic options that are appropriate for your organization.

You can also implement additional features to help enhance security in e-mail messaging. For example, you can provide security labels that match your organization's security policy. An Internal Use Only label might be implemented as a security label to apply to e-mail messages that are not to be sent or forwarded outside your company.

For more information, see Plan for e-mail messaging cryptography in Outlook 2010.

Restricting permission on e-mail messages

Information Rights Management (IRM) helps users prevent sensitive e-mail messages and other 2007 Office system content, such as documents and worksheets, from being forwarded, edited, or copied by unauthorized people. In Outlook 2010, users can use IRM to mark e-mail messages with "Do not forward," which automatically restricts permission for recipients to forward, print, or copy the message. In addition, you can define customized Office-wide IRM permission policies for your organization's needs and can deploy the new permission policies for users to use with e-mail messages or other Office documents. For more information, see Plan for Information Rights Management in Office 2010.

Outlook 2010 and e-mail protocols and servers

Outlook 2010 can be used with many e-mail servers and services. The primary e-mail servers and services supported by Outlook include the following:

  • Simple Mail Transfer Protocol (SMTP)

  • Post Office Protocol version 3 (POP3)

  • Internet Mail Access Protocol version 4 (IMAP4)

  • Messaging Application Programming Interface (MAPI) for Exchange Server (version 2003 and later)

  • Other messaging and information sources, including Hewlett-Packard OpenMail. Use of these additional service providers is made possible by the way in which Outlook 2010 uses the MAPI extensibility interface.

HTTP is supported with the installation of the Outlook Connector.

Users can use Outlook 2010 without an e-mail server to use the Contacts, Tasks, and Calendar features in a stand-alone configuration.

Upgrading from an earlier version of Outlook

You can install Outlook 2010 over any previous installation of Outlook. As in other Office 2010 applications, user settings that are stored in the registry are migrated. If a MAPI profile already exists on a user's computer, you typically can configure a deployment to continue using the profile. However, if you are upgrading from an Internet Mail Only installation of Outlook 2000 or earlier, you might have to re-create user profiles.

Outlook 2010 cannot coexist with previous versions of Outlook on the same computer. If you determine that users need an earlier version, do not install Outlook 2010 or deploy Outlook 2010 with application virtualization.

When you upgrade users from an earlier version of Outlook, you must make choices about how to configure user profiles, consider Cached Exchange Mode issues, and be aware of fax and forms changes.

For an overview of feature changes and migration considerations, see Changes in Outlook 2010 (for IT pros).

Upgrading to Office 2010 with Cached Exchange Mode enabled

The process of upgrading users who currently have Cached Exchange Mode enabled in either Office Outlook 2003 or Office Outlook 2007 is straightforward. If you do not change Cached Exchange Mode settings, the same settings are kept for Outlook 2010. There is no change to the .ost or OAB file format, and you do not have to re-create these files during an upgrade.

However, if ANSI Outlook data files (.ost) are in the organization’s environment, you might have to take additional steps when you migrate files to Outlook 2010. Users who have non-Unicode (ANSI) formatted data files (.ost) and large Exchange mailboxes can experience errors when Outlook attempts to synchronize their mailboxes to their .ost files. We recommend that you upgrade users’ .ost files to the Unicode format because Outlook Unicode files do not have the 2-gigabyte (GB) size limit of Outlook ANSI files. Unicode is the default file format for Outlook 2010. For information about how to force an upgrade of an existing non-Unicode (ANSI) formatted .ost file to Unicode format, see the section “To force upgrade of non-Unicode ANSI format .ost files to Unicode” in the article Configure Cached Exchange Mode in Outlook 2010.

For additional Cached Exchange Mode planning considerations, see Plan an Exchange deployment in Outlook 2010.

Additional considerations when planning an upgrade

To prepare for an upgrade, you must determine answers to the following additional questions:

Upgrading from other mail and scheduling programs

You can upgrade to Outlook 2010 from other e-mail and scheduling programs. The process can be simplified by using the Import feature in Outlook.

The following table lists migration paths supported by Outlook 2010.

Software program Version

Outlook Express

4. x, 5. x, 6. x

Eudora Pro, Eudora Light

2. x, 3. x, 4. x, 5. x, 6. x, 7. x


You cannot import Microsoft Mail files to Outlook 2010, and you cannot share information between Outlook 2010 and Schedule Plus.