Installing Exchange 2010 Service Pack 1 Fails At Mailbox Role: Database is mandatory on UserMailbox.

In a recent incident, an Exchange server had a complete volume failure during testing. Exchange 2010 was reinstalled but when installing Service Pack 1, it failed upgrading the Mailbox Role. Upon reviewing the log, I found the following line:

Database is mandatory on UserMailbox. Property Name: Database

The error doesn’t explain the problem very well but it is basically saying that there is a UserMailbox without a database, which should never happen. The failure of the volume and subsequent reinstall of 2010 left the arbitration mailboxes (and one or two user mailboxes) orphaned. Most of the suggestions to resolve this problem list doing things like deleting the system mailboxes and running “ /PrepareAD”. After looking around, I was able to parse together a few other options and find a fix.

First, do a search in AD for the System mailboxes and make sure they exist in AD. (If they do not exist, check out this blog.)The three mailboxes are:

  • Discovery – SystemMailbox{e0dc1c29-89c3-4034-b678-e6c29d823ed9}
  • Message Approval – SystemMailbox{1f05a927-xxxx-xxxx-xxxx-xxxxxxxxxxxx} (where x is a random number)
  • Federated E-mail – FederatedEmail.4c1f4d8b-8179-4148-93bf-00a95fa1e042

Next, check out the status of their mailboxes:

Get-Mailbox –Arbitration

For this client, their Discovery and Message Approval mailboxes spat out error messages:

WARNING: The object XXXXXXXX.XXXXX/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.

The fix is a lovely, one-line powershell. It won’t do anything without prompting you first. To verify it fixes the issue after you run it, take the first half of the command (get-mailbox -arbitration) and run that again to confirm they are online and okay.

Get-Mailbox -Arbitration | Set-Mailbox -Arbitration –Database "Mailbox Database XXX"

Hopefully this saves somebody from causing a bigger mess than necessary. After running this, I was able to install Service Pack 1 just fine. YMMV.

Edit: I found the DiscoverySearchMailbox{D919BA05-46A6-415f-80AD-7E09334BB852} was orphaned as well. To fix this mailbox, I just ran the following PoSH.

Get-Mailbox -Identity "DiscoverySearchMailbox{D919BA05-46A6-415f-80AD-7E09334BB852}" | Set-Mailbox –Database "Mailbox Database XXX"