Microsoft KB Archive/307926

Knowledge Base

Outlook Clients Cannot Connect to an ISA Server-Published Exchange 2000 Server

Article ID: 307926

Article Last Modified on 9/12/2007

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APPLIES TO

• Microsoft Internet Security and Acceleration Server 2000 Standard Edition
• Microsoft Outlook 2000 Standard Edition
• Microsoft Outlook 2000 Service Pack 1
• Microsoft Outlook 98 Standard Edition

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This article was previously published under Q307926

SYMPTOMS

If you try to connect from an Outlook 98 or an Outlook 2000 Service Pack 2 (SP2) client to an Exchange 2000 server that was published by using ISA Server Publishing, you may not successfully connect.

If you create a new profile, you may receive the following error message:

The name could not be resolved. The server containing the Global Address List is no longer available. You can reconnect to a different server by restarting Outlook or retry the operation when the server is reachable.

Or, when you try to connect, you may receive the following error message:

Unable to open your default e-mail folders. The attempt to log on to the Microsoft Exchange Server computer failed.

CAUSE

This behavior occurs because the connection behavior in Outlook 98 and Outlook 2000 SP2 has changed to enable the load balancing of the global catalog servers. When the Outlook client starts, it asks the Exchange 2000 server for a global catalog server. This query may interrupt the Server Publishing of Exchange 2000 remote procedure call (RPC) servers because, for security reasons, the Microsoft Internet Security and Acceleration (ISA) RPC Filter only maps RPC endpoint connections. The RPC Filter in ISA gracefully terminates the connection when it receives this query.

WORKAROUND

WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.
To work around this behavior, you must hardcode the global catalog name for each client that you want to connect to the Server Published Exchange 2000 server. This hardcoded global catalog server is defined on a per user basis.

To hardcode the Outlook client to use the same name as the clients use to connect to Exchange 2000 when Server Published through ISA, use the following steps:

1. Click Start, click Run, type regedt32 to open the Registry Editor, and then click OK.
2. Locate, and then click the following key in the registry:

   HKEY_CURRENT_USER\Software\Microsoft\Exchange\Exchange Provider

   Note: You may have to create both the Exchange key and the Exchange Provider key.
3. On the Edit menu, click Add Value, and then add the following registry value:
   Value name: DS Server
   Data type: REG_SZ
   Value data: GC server name
4. Quit the Registry Editor.

STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.

MORE INFORMATION

For additional information, click the following article number to view the article in the Microsoft Knowledge Base:

272290 OL2000: Outlook Load Balancing with Global Catalog Servers

Keywords: kbprb KB307926

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