If you have used ADMT and PowerShell for a cross domain migration, some mailboxes are listed as linked mailbox.
I have searched a whole fuc..ing night to figure out what caused this linked mailbox behavior!
Here the Solutions:
Make sure, that on the source server, no unmatched SID on the advanced Exchange Security Permission and Owner TAB are listed!
On SOURCE Server
- Show Advanced Features in ADUC
Open the user with the mailbox migrated as linked mailbox => Click on Exchange – Advanced => Click on Mailbox rights, Make sure no unmatched SID is listed
Also open Advanced => Owner and Make sure the Owner still exists and has also been migrated to the targed Host!
