Recently one of our customers logged a ticket with the following error when trying to send mail to an all users group that has moderation on:
“This message can’t be moderated because the approval system is too busy and can’t accept messages now. Please try resending this message later, or contact the recipient directly.”
Followed by:
“SystemMailbox{1f05a927-27a6-40d9-8bc0-878553dc4ea9}@XXX.local<mailto:SystemMailbox%7b1f05a927-27a6-40d9-8bc0-878553dc4ea9%[email protected]> #550 4.4.7 QUEUE.Expired; message expired in unreachable destination queue. Reason: The mailbox recipient does not have a mailbox database ##”
Step 1: Lets check Exchange.
Launch the Exchange Management Shell (EMS) and run the following command:
- Get-Mailbox -Arbitration
When you run this it should provide you with the 3 Arbitration mailboxes, however in this case the following error was returned:
“SystemMailbox{1f05a927… SystemMailbox{1f0… XXX unlimited
WARNING: The object XXX.local/Users/SystemMailbox{1f05a927-20f4-466a-9c6a-240a65a5a644} has been corrupted, and it’s in an inconsistent state. The following validation errors happened:
WARNING: Database is mandatory on UserMailbox.
WARNING: Database is mandatory on UserMailbox.
SystemMailbox{e0dc1c29… SystemMailbox{e0d… XXX unlimited
WARNING: The object XXX.local/Users/SystemMailbox{e0dc1c29-89c3-4034-b678-e6c29d823ed9} has been corrupted, and it’s in an inconsistent state. The following validation errors happened:
WARNING: Database is mandatory on UserMailbox.
WARNING: Database is mandatory on UserMailbox.”
If you try running the command Enable-Mailbox on one of these you will get an error as well.
The solution:
Let’s re-home the Arbitration Mailboxes. To do this run the following command in the EMS:
- Set-Mailbox -Arbitration -Identity “Migration.8f3e7716-2011-43e4-96b1-aba62d229136” –Database “DB Name”
Do the same for all the other ones. Once complete, we will re-run the command again to check the Arbitration Mailboxes:
Now they are showing just fine. All moderation will now work again.
An Alternative Solution:
You can go into Active Directory Users and Computers, locate the 4 accounts located under the Users directory and delete them.
Once that is complete, you can re-run the Exchange Setup and just PrepareAD again and it will re-create all of them for you.
Hope it helps.