Recreate missing arbitration user accounts and mailboxes in Exchange Server 2010

If the arbitration users and mailboxes are missing, these accounts needs to be recreated and enabled for audit logs to work again.

There are a number of accounts that you might have to recreate. All these can be found in the “Users” OU in Active Directory. They should look something like this:

1. Federated

2. Email.4c1f4d8b-8179-4148-93bf-00a95fa1e042

3. SystemMailbox{1f05a927-af78-475a-aba4-fc281398eb54}

4. SystemMailbox{e0dc1c29-89c3-4034-b678-e6c29d823ed9}

Get-Mailbox –Arbitration

You will have to use the Exchange 2010 setup and run PrepareAD and the process will add the missing accounts again.

setup.com /PrepareAD

Then

Use the following command to enable the mailboxes:

Enable-Mailbox –Arbitration –Identity “FederatedEmail.4c1f4d8b-8179-4148-93bf-00a95fa1e042”

Enable-Mailbox –Arbitration –Identity “SystemMailbox{1f05a927-8668-4003-adad-9b80758e86db}”

Enable-Mailbox –Arbitration –Identity “SystemMailbox{e0dc1c29-89c3-4034-b678-e6c29d823ed9}”

You should also reset the quota for the “FederatedEmail.4c1f4d8b-8179-4148-93bf-00a95fa1e042” mailbox. This can be done using the following command:

Set-Mailbox –Arbitration –Identity “FederatedEmail.4c1f4d8b-8179-4148-93bf-00a95fa1e042” –ProhibitSendQuota 1MB

Once you have finished these commands you should be all set. If you want to make sure that the commands really worked you can list the arbitration mailboxes by using the following command:

Get-Mailbox –Arbitration

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