We had an issue recently where our customers Exchange 2010 servers arbitrations mailboxes had become corrupt and were giving the below errors when running “Get-mailbox –arbitration”
WARNING: The object 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.
To resolve this we had to run through the following steps
- Open AD Users and Computers
- Expand the Domain go to users OU
- Find the following accounts and delete them
- “SystemMailbox{e0dc1c29-89c3-4034-b678-e6c29d823ed9}”
- “FederatedEmail.4c1f4d8b-8179-4148-93bf-00a95fa1e042”
- “SystemMailbox{1f05a927-****-****-****-*******}” (Make a note of the Guid of previous system mailbox as it varies on every enviroment)
- Open Command prompt navigate to your Exchange Setup files and run setup.com /preparead
- Open the Exchange Management Shell and run the below
- Enable-Mailbox –Arbitration –Identity “FederatedEmail.4c1f4d8b-8179-4148-93bf-00a95fa1e042”
- Enable-Mailbox –Arbitration –Identity “SystemMailbox{e0dc1c29-89c3-4034-b678-e6c29d823ed9}”
- Enable-Mailbox –Arbitration –Identity “SystemMailbox{1f05a927-****-****-****-*******}” (Remember to change *** to your Guid)
- Set-Mailbox –Arbitration –Identity “SystemMailbox{e0dc1c29-89c3-4034-b678-e6c29d823ed9}” –DisplayName “Microsoft Exchange”
- Set-Mailbox –Arbitration –Identity “FederatedEmail.4c1f4d8b-8179-4148-93bf-00a95fa1e042” –ProhibitSendQuota 1MB
Your arbitration mailboxes should now be fine, run Get-Mailbox –arbitration to confirm and all should appear with no errors 
