Error with moving mailbox in Exchange 2010 SP2 RU3+

I was working with a customer today who had recently migrated to Exchange 2010 SP2 RU5 from Exchange 2007 and they had an issue when they were trying to move mailboxes between Exchange 2010 databases. Although the move did complete, it "Completed with Warnings" showing the following error in the move request details:

Warning: Failed to clean up the source mailbox after the move.

Error details:
MapiExceptionUnexpectedMailboxState: Unable to delete mailbox. (hr=0x80004005,ec=2634)

 

When we looked around a little bit, we found that all the mailboxes that had completed with this particular error ended up having a disconnected mailbox showing up in the Exchange Management Console.

With a little bit of research, I found that this is a bug that applies to Exchange 2010 SP2 RU3, RU4, and RU5. You can prevent this issue from happening in the future by upgrading to Exchange 2010 SP3. However, you still need to get those disconnected mailboxes out of there. To do this, you want to use the following commands in Exchange Management Shell:

1.) Run the command to find the specific mailboxes that were impacted by this bug.

Get-MailboxStatistics -Database <MAILBOXDATABASE> | Where { $_.DisconnectReason -eq "SoftDeleted" } | fl LegacyDN, DisplayName, MailboxGUID,DisconnectReason

 2.) Run this command to remove those disconnected mailboxes cleanly.

Remove-StoreMailbox –Database <MAILBOXDATABASE> –Identity <MAILBOXGUID> –MailboxState Softdeleted

 

After running these steps, we were able to successfully cleanup those disconnected mailboxes.