I recently had a interesting issue where I was seeing the 1121 error below in the Application log on one of my Exchange 2013 servers every minute.
Log Name: Application
Source: MSExchange Mailbox Replication
Date: 14/01/2015 2:23:34 p.m.
Event ID: 1121
Task Category: Request
The Microsoft Exchange Mailbox Replication service was unable to process a request due to an unexpected error.
Request GUID: '60b5375b-0f27-4561-a0f2-af428dd3c501'
Database GUID: '43ce3977-2c7f-4c6a-937b-b94966c81122'
Error: An Active Directory Constraint Violation error occurred on dc1.contoso.com. Additional information: The name reference is invalid.
This may be caused by replication latency between Active Directory domain controllers.
Active directory response: 000020B5: AtrErr: DSID-03152CB1, #1:
0: 000020B5: DSID-03152CB1, problem 1005 (CONSTRAINT_ATT_TYPE), data 0, Att 9fc1287c (msExchMailboxMoveSourceMDBLink)
--> A value in the request is invalid..
The reference to “msExchMailboxMoveSourceMDBLink” was the only indication the error related to a mailbox move request. Frustratingly, no requests showed up from running Get-MoveRequest.
After some ineffective troubleshooting I eventually found the solution from Exchange MVP Jeff Guillet. The error message he shows in his article is different to mine, but the fix is the same.
I had to run the following command:
Remove-MoveRequest -MoveRequestQueue '43ce3977-2c7f-4c6a-937b-b94966c81122' -MailboxGuid '60b5375b-0f27-4561-a0f2-af428dd3c501'
I still don’t know the cause of the problem, but I have a suspicion it followed a reverse mailbox move from Exchange 2013 (CU6) to Exchange 2007 (SP3 RU13).
Hopefully this helps if you ever come across the same issue.