Topic Last Modified: 2007-05-01
The Microsoft® Exchange Server Analyzer Tool reads the following registry entry to determine whether MAPI client blocking has been set:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MSExchangeIS\ParametersSystem\Disable MAPI Clients
If the Exchange Server Analyzer finds that the value for Disabled MAPI Clients is set with a value that blocks all MAPI clients in the ranges of 6 through 9, the Exchange Server Analyzer displays a warning.
By default, the Disable MAPI Clients key is not enabled. By enabling this key an administrator can block specific versions of Microsoft Office Outlook® from connecting to a computer that is running Exchange 2000 Server, Exchange Server 2003, or Exchange Server 2007.
When the Disabled MAPI Clients key is set with a value that blocks MAPI clients in the range of 6 through 9, entire ranges of MAPI versions are blocked. These ranges correspond to the Outlook 2000, Outlook 2003, and Outlook 2007 versions and to Exchange System Attendant in Exchange Server 2003. Blocking the Exchange System Attendant service will likely cause Exchange Server to malfunction.
To fix this warning, follow the recommendations and procedure in All versions of Outlook are allowed to access the server.
For more information about blocking specific MAPI clients from connecting to a computer that is running Exchange 2000 Server or Exchange Server 2003, see the following Microsoft Knowledge Base articles:
- 328240, "How to put server-side restrictions on clients that
are used to access Exchange 2000 mailboxes" (http://go.microsoft.com/fwlink/?linkid=3052&kbid=328240)
- 288894, "How to disable MAPI client access to an Exchange
Server 2003 computer or to an Exchange 2000 Server computer"
For more information about blocking specific MAPI clients from connecting to a computer that is running Exchange Server 2007, see the Exchange Management Shell "Set-CasMailbox" cmdlet in the Exchange Server 2007 product documentation (http://go.microsoft.com/fwlink/?LinkId=80698).
For more information about how to download security updates for older versions of Outlook and blocking other versions of Outlook, see Slowing and Stopping E-Mail Viruses in an Exchange Server 2003 Environment (http://go.microsoft.com/fwlink/?LinkId=30732).