In Exchange, when you are working with a legacy system and migrating mailboxes to the new Exchange Server, you will find that you cannot remove the database on the server as it gives you some long error message it still contains archives mailboxes etc.

To move all the system, federation and migration mailboxes (arbitration), you can firstly find them with a simple command:

  • get-mailbox -server exchange-2016 -Arbitration

The above is looking at the Exchange 2016 server and has the -Arbitration switch at the end as we are looking for all those mailboxes:

As shown above you can see the list of them, now the next step is to just extend on the command above and move them to the Exchange 2019 server using this command:

  • get-mailbox -server exchange-2016 -Arbitration | New-MoveRequest -TargetDatabase “Mailbox Database 0188089110”

The extra piece we adding on is the New-MoveRequest command and we are specifying a database on the Exchange 2019 Server.

The process from here on is the same as checking normal mailbox moves. You can check the progress running the following commands:

  • Get-MoveRequest | Get-MoveRequestStatistics

As shown above, you can see all the arbitration mailboxes have now been moved across and you can continue with you cleanup. You need to remove the move requests as well.

Hope it helps.