Your attempt to generate an offline address list does not work and Event 9126 occurs in Exchange 2000 Server and Exchange Server 2003

In Exchange 2000 Server and Exchange Server 2003, when you try to generate an offline address list that is based on the Global Address List or on any other existing address list, the list may not be generated. The following information is recorded in the Application log:
When the generation of offline address lists fail, you may receive the following error message in Exchange System Manager:

This behavior can occur if the relevant registry key contains an invalid DS Server value that is specified with the name of a particular domain controller/global catalog server. The relevant registry key is: You can use this registry entry on a client computer to load-balance or to specify which domain controller/global catalog server the Outlook client connects to. However, if this value is incorrect on an Exchange 2000 Server SP2 computer, generation of an offline address list generation does not succeed.

Warning Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall your operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.

To resolve this behavior, delete the DS Server value from the Exchange Provider key. Make sure that you remove the entire value from the key, not just the value data. Follow these steps:

1. Start Registry Editor (Regedt32.exe).
2. Locate the DS Server value under the following key in the registry:
   HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Exchange\Exchange Provider
3. Click DS Server, click Edit, and then click Delete. Click Yes to confirm the deletion.
4. Quit Registry Editor.