MAPI interface disabled on global catalog

[This topic is intended to address a specific issue called out by the Exchange Server Analyzer Tool. You should apply it only to systems that have had the Exchange Server Analyzer Tool run against them and are experiencing that specific issue. The Exchange Server Analyzer Tool, available as a free download, remotely collects configuration data from each server in the topology and automatically analyzes the data. The resulting report details important configuration issues, potential problems, and nondefault product settings. By following these recommendations, you can achieve better performance, scalability, reliability, and uptime. For more information about the tool or to download the latest versions, see "Microsoft Exchange Analyzers" at]  

Topic Last Modified: 2005-11-17

The Microsoft® Exchange Server Analyzer Tool reads the following registry key to determine that the registry key exists:

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\NTDS\Parameters\Initialize MAPI interface

If the Exchange Server Analyzer finds the Initialize MAPI interface key is present and configured to have any numeric value, the Exchange Server Analyzer displays an error.

When the Initialize MAPI interface registry key is present Microsoft Office Outlook® clients will not be able to contact the address book on this server. To correct this problem you must remove the Initialize MAPI interface registry key.


This article contains information about editing the registry. Before you edit the registry, make sure you understand how to restore the registry if a problem occurs. For information about how to restore the registry, view the "Restore the Registry" Help topic in Regedit.exe or Regedt32.exe.

To correct this warning

  1. Open a registry editor, such as Regedit.exe or Regedt32.exe.

  2. Navigate to: HKLM\System\CurrentControlSet\Services\NTDS\Parameters\Initialize MAPI interface

  3. Right-click the Initialize MAPI interface key and select Delete.

  4. Close the registry editor and restart the Exchange server.

Before you edit the registry, and for information about how to edit the registry, see Microsoft Knowledge Base article 256986, "Description of the Microsoft Windows registry" (

For more information about the Initialize MAPI interface.registry key see Microsoft Knowledge Base article 275127, "XADM:How to Configure Exchange Server 5.5 to Run on a Domain Controller that is a Global Catalog" (