We were in the process of moving mailboxes from an Exchange 2003 server to 2010. All of a sudden a move request failed.
On looking at the 2003 Exchange server the mailbox was not there. On the 2010 EMC there was a mailbox with the right name but it was showing as being on the old server.
Also in the 2010 EMC console there was a disconnected mailbox with the right name.
To fix the issue the following was carried out :
1) On the 2003 Mailbox Store do a mailbox cleanup a couple of times.
2) Open a EM Shell and do
Clean-MailboxDatabase I used the Database name from the disconnected mailbox.
3) After a while the live mailbox in mailboxes was showing the exchange 2010 server.
4) Do a local move request back to the Exchange 2003 server. This fails straight away.
5) Then run the command
Clean-MailboxDatabase (Same as database in 2)
6) This might take a while to run (Mine took 45 mins to complete)
7) Close EMC (Refreshing didn’t seem to update view)
8) Re-open EMC
Job done