XADM: Replication or Knowledge Consistency Check Fails with Application Event ID 1091 (166312)

SYMPTOMS

When attempting to perform a knowledge consistency check (KCC), you receive the following warning:

An error was encountered by the knowledge consistency checker on server
'ServerName'. <<0xc1030b1e - The knowledge consistency check did not
correct directory inconsistencies. Be sure the directory service is
running, and then try again. If the error recurs, try stopping the
directory service and the Administrator program and then restarting
them. To view details of the error, see the application event log in
the Windows NT Event Viewer on the Microsoft Exchange Server computer
on which you checked knowledge consistency.

You will also receive the following replication error in the application log:

   Event ID: 1091
   Source: MSExchangeDS
   Type: Warning
   Category: Replication

   The directory replication agent (DRA) attempted to open mail with name
   /o=Organization/ou=SITE/cn=Configuration/cn=Servers/cn=ServerName/cn=
   Microsoft DSA:ServerName but received error 2147942487. Messages could
   not be sent. Make sure that the mail service on this Microsoft Exchange
   Server computer is running.

MORE INFORMATION

Error 2147942487 is a Jet-level error indicating that an invalid MAPI parameter has been passed on by the messaging service (MAPI_E_INVALID_PARAMETER). This could happen if Mapi32.dll is not a supported version or the latest version supplied with Exchange or the latest service pack.

RESOLUTION

Stop all Exchange services and copy the Mapi32.dll file from the Exchange Server 5.0 CD. Replace the Mapi32.dll file in the \<system>\system32 with the correct Mapi32.dll file. Remove the read-only attribute on the Mapi32.dll file and restart the Exchange services.