After you’ve installed a new Exchange 2010 environment and you try to delete the first automatically created mailbox database, you’ll receive the following error.
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The mailbox database ‘DB01’ cannot be deleted.
DB01
Failed
Error:
This mailbox database contains one or more mailboxes or arbitration mailboxes. To get a list of all mailboxes in this database, run the command Get-Mailbox -Database <Database ID>. To get a list of all arbitration mailboxes in this database, run the command Get-Mailbox -Database <Database ID> -Arbitration. To disable a non-arbitration mailbox so that you can delete the mailbox database, run the command Disable-Mailbox <Mailbox ID>. Arbitration mailboxes should be moved to another server; run the command Move-Mailbox <Mailbox ID> -Arbitration -TargetDatabase <Database ID>. To remove the arbitration mailbox if this is the last server in the organization, run the command Remove-Mailbox <Mailbox ID> -Arbitration -RemoveLastArbitrationMailboxAllowed.
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You cannot remove the database, because there are some mailboxes in it. Oké….let’s have look what mailboxes are left in this mailbox database.
Get-Mailbox -Database DB01
As you can see, there are no mailboxes left in de mailbox database, but why we are still receiving this error!! This is the answer…….there are two hidden mailboxes left in de mailbox database, called arbitration mailboxes. With the following command you’re able to see this mailboxes
Get-Mailbox -Database DB01 -Arbitration | ft -wrap -auto
When you move these two mailboxes to another mailbox database, all the error messages are gone! So let’s do that!
Move-Mailbox “SystemMailbox{1f05a927-3be2-4fb9-aa03-b59fe3b56f4c}” -Arbitration -TargetDatabase DB02
Move-Mailbox “SystemMailbox{e0dc1c29-89c3-4034-b678-e6c29d823ed9}” -Arbitration -TargetDatabase DB02
