Deployment Scenarios for Outlook 2003

This topic discusses a variety of offline address book best practices to use when deploying Microsoft® Office Outlook® 2003. In addition, this topic also discusses offline address book best practices to use when upgrading from Microsoft Exchange Server 5.5, performing site consolidations and mergers, and for staging offline address book deployments.

General Recommendations When Upgrading Exchange Server or Outlook Versions

Upgrading Exchange Server and Outlook clients at the same time can potentially cause severe network congestion. For example, upgrading your Exchange organization to Offline Address List version 4 (OAB v4) (that is, upgrading your offline address book servers to Exchange Server 2003 Service Pack 2 (SP2) and your clients to Outlook 2003 SP2), may cause significant network usage and latency problems if you perform the server and client upgrades in a short period of time. To minimize the network congestion when you upgrade your servers and clients, consider the following:

• Set the offline address book download threshold appropriately on Exchange Server. For detailed steps regarding how to configure this setting, see Microsoft Knowledge Base article 867623 "Throttling full offline Address Book downloads to limit the effect on a LAN in Exchange Server 2003."

• Stage the rollout of Outlook clients over a period of time. If you upgrade all clients on the same day, network congestion can have an adverse effect on the network.

Upgrading from Exchange Server 5.5

There are several factors to consider when upgrading to Exchange Server 2003 from Exchange Server 5.5. From the perspective of Outlook 2003, the Active Directory® directory service provides data previously provided to Outlook by the Exchange Server 5.5 directory. This data includes the global address list (GAL), address book views, and offline address books. There are significant differences in the implementation of offline address books in Exchange Server 2003 and Exchange Server 5.5. Exchange Server 5.5 generates site-specific offline address books in ANSI format from recipient information in the Exchange Directory. Exchange Server 2003 generates organization-specific offline address books from Active Directory objects. There is no upgrade or synchronization of offline address books between Exchange Server 2003 and Exchange Server 5.5.

You may need to perform the following tasks during and after the upgrade, depending on your existing Exchange Server 5.5 topology:

• Move offline address books to another Exchange Server 5.5 computer in the site until the last one is decommissioned.

• Re-create user Outlook profiles to change from ANSI to Unicode offline address books.

Moving Exchange Server 5.5 Offline Address Books

Users with mailboxes on an Exchange Server 5.5 computer can only download offline address books that an Exchange Server 5.5 computer generated. As long as Exchange Server 5.5 computers exist in the site or administrative group, offline address books cannot reside on an Exchange Server 2003 computer. As a best practice, you should move the offline address books to an Exchange Server 5.5 computer in the site that you are planning to decommission last.

For detailed instructions, see How to Move the Offline Address Book in Exchange Server 5.5.

By default, the first server in the Exchange site assumes the role of the offline address book server holding the offline address books for all MAPI-based clients. Offline address books should remain on an Exchange Server 5.5 computer as long as there are users in the organization that are still using Exchange Server 5.5. Exchange maintains offline address books in system folders, which are hidden public folders.

Re-Create User Outlook Profiles

After you move your Exchange Server 5.5 mailboxes to a computer that is running Exchange Server 2003, a user's offline address book files remain in ANSI format, even though the Exchange Server 2003 computer has created an offline address book in Unicode format. To use the new Unicode format, you can either manually re-create each user's Outlook profile, or use the Office 2003 Resource Kit group policy to configure and deploy group policies that control offline address book downloads and format. After a new profile is created, a Unicode offline address book can be downloaded.

For more information about how to create a new Outlook profile for Outlook 2003, see Microsoft Knowledge Base article 829918, "How to create a new e-mail profile in Outlook 2003." For more information about using the Office 2003 Resource Kit to control offline address book format, see the Office 2003 Resource Kit.

Upgrading to Exchange Server 2003 SP2 and Office Outlook 2003 SP2

You do not need to upgrade your offline address book servers to Exchange Server 2003 SP2 and your Outlook 2003 clients to Outlook 2003 SP2 at the same time. Additionally, the order in which you upgrade your offline address book servers and Outlook 2003 SP2 clients is irrelevant, allowing you to control your deployment plans. For general considerations when you upgrade offline address book versions, see "General Recommendations When Upgrading Exchange or Outlook Versions" earlier in this topic.

Exchange Server 2003 and Office Outlook 2003 Offline Address Book Compatibility

The following table illustrates the compatibility matrix as it applies to the offline address book feature in Exchange Server 2003 and Office Outlook 2003. Use this table to determine which version of the offline address book will be used by a particular mix of Outlook and Exchange Server.

Site Consolidation

In addition to its many benefits, one of the typical side effects of site consolidation is increased physical distance between Outlook clients and the Exchange Server public folder containing the offline address book. As mentioned previously, the size of the offline address book and the impact on the network is a concern for large organizations, especially those that have consolidated Exchange servers into a regional datacenter. Usually, from day-to-day, there should not be a large number of Outlook clients that download the full offline address book. However, there are situations that can cause an increased number of Outlook clients to download the full offline address book. Because the cost of downloading the full offline address book is high, you should understand these situations and reduce their occurrence as much as possible.

In a site consolidation scenario, one way to reduce these costs is to deploy a remote offline address book-only server. A remote offline address book-only server is a typical Exchange public folder server with no public folder content except for a local offline address book. Because the offline address book-only server stores only the offline address book, it does not need to be backed up, and any downtime by the server will not affect Outlook performance. If the server is unavailable, the only impact will be that Outlook cannot get an updated offline address book until the server issue is addressed.

After the server is set up, each Outlook client needs to be directed to it. This can be accomplished by means of two techniques:

• Configure the mailbox store to use the specific offline address book. In most consolidation scenarios, this choice is not feasible because the mailbox store typically contains mailboxes consolidated from many sites.

• Configure the individual mailboxes to a specific remote offline address book server. This is accomplished by adding an Active Directory attribute, msExchUseOAB, on each Active Directory account for these mailboxes to reference the specific offline address book.

The general process for setting up an offline address book-only server is the following:

1. Install Exchange on a computer at a remote location and prepare the server for the offline address book. Leave the mailbox stores on the server for the system attendant mailbox, but do not add any mailboxes to the server. A public folder store is also required and will be created during setup.

2. Using Exchange System Manager, create the offline address book on the remote server:

   • Create a new offline address book, and select the remote server as the offline address list server.

   • Allow the server to create the offline address list. The offline address book is not created at the time you configure the options, but during its scheduled maintenance period.

   • If you have previously created offline address books, use Exchange System Manager to make sure that the only server that has the offline address book public folders is the remote server. You may need to manually configure the folders to have replicas on the remote server.

3. Configure mailboxes to use the remote offline address book. You can direct all mailboxes on a specific store to the remote offline address book by configuring the store properties. You can also use ADSI Edit, LDIFDE, or a script, to set the MSExchUseOAB Active Directory attribute for each object that you want to direct to this specific offline address book.

   Note

   This is a directory link, and it should be set to the distinguished name of the msExchOfflineAddressList object.

Merging of Directory Services

When two or more companies merge their organizations, and in particular merge or synchronize their Active Directory services, it is common for the global address list to grow larger, which causes offline address book files to grow larger. In mergers of large organizations, the size of the global address book can increase by 100 percent or more. Depending on the rate at which changes are entered, replicated, and written to the offline address book, and depending on the number of offline address book users in the merged organization, such an increase in size could have a significant impact on the network and the public folder servers that host the offline address book.

To minimize the impact that a significant increase in the size of offline address book files can have on a wide area network (WAN), deploy a dedicated offline address book server as previously described.

Offline Address Book Staging

Staging offline address book files to Outlook clients can also allow them to operate in Cached Exchange Mode without having to resolve names using a global catalog server.

You have two choices for staging offline address book files on client computers:

• You can manually deploy the offline address book data to remote clients. For more information about this approach, see "Manually Deploying Offline Address Books" later in this topic.

• You can deploy the data using tools from the Office 2003 Resource Kit. You can use the Custom Installation Wizard and the Office Profile Wizard from the Office 2003 Resource Kit to deploy offline address book files and relevant registry keys during the installation of Outlook. For more information about how to automate the deployment of offline address book data to Outlook clients, see the Office 2003 Resource Kit.

Manually Deploying Offline Address Books

Manually deploying offline address books requires you to use a staging computer. After the offline address book files have been downloaded to the staging computer, these files and the offline address book registry entries are manually copied to one or more Outlook 2003 computers. The copy process can occur over the network, using a CD-ROM, or by means of some other file transfer method. Use the following procedures to manually deploy offline address books.

1. How to Create Offline Address Book Files on a Staging Computer

2. How to Copy the Offline Address Book Files from the Test Computer to the Intended Outlook Computers

3. How to Deploy the Sequence Number for the Offline Address Book Data Created on the Test Computer

If you want the Outlook clients to perform differential offline address book downloads, starting from the offline address book data being deployed, you will need to also deploy the sequence number for the offline address book data created on the test computer before starting the Outlook client as described earlier in Step 6 of "To copy the offline address book files from the test computer to the intended Outlook computers."

Specifying the Versions of Offline Address Book to Be Generated

You do not need to configure Exchange Server 2003 to generate offline address book files that you do not need. On servers running Exchange Server 2003 SP2 and later, you can specify the versions of the offline address book to be generated. You make this specification by configuring the doOABVersion attribute of the Offline Address Lists object in the Address Lists container in Active Directory.

By default, on servers running Exchange Server 2003 SP2, OAB v2, v3a, and v4 files are generated. On servers running Exchange Server 2003 SP1, OAB v2 and v3a files are generated.

For detailed information about how to specify the versions of offline address book files to be generated, see How to Specify the Versions of Offline Address Book to Be Generated.

For information about the differences between OAB v2, v3a, and v4, see Improvements for Offline Address Books.