While backing up a Mailbox, the job will complete successfully but your Cirrus Backup logs say completed with a warning: Failed to find group owner account. 


A team you are trying to backup does not have an owner attached and you see the following error message in your Cirrus Backup session logs:

Failed to process team: <Team Name>. Failed to find Team mailbox owner account.


Cirrus uses impersonation to backup items in Microsoft 365, without an owner Cirrus is unable to impersonate a Microsoft 365 Teams. If no owner is assigned it is seen as an orphaned group. 


Please assign an owner to each of the Office 365 Teams you wish to have backed up. The steps to achieve this can be found in this Microsoft article. Alternatively, you can exclude those Teams from being backed up if it is not necessary.


If you are unsure of how to check your backup session logs, please see the View Backup Logs knowledge base article.

Help & Support

If you have followed the steps outlined above and the issue recurs in the next backup cycle, or you need help performing these changes, you can access online help at