When running Veeam Backup for Microsoft Office 365, you may occasionally encounter warnings such as:
Processing mailbox Archive completed with warning: Failed to find group owner account
Processing mailbox Buildings completed with warning: Failed to find group owner accountThis issue occurs when the backup process tries to access and process unified groups (Microsoft 365 Groups), but no valid group owner is associated with them. Veeam uses group ownership to address permissions, and the absence of an owner can disrupt the backup process.
To verify ownership, we can use the Exchange Online PowerShell command:
Connect-ExchangeOnline
Get-UnifiedGroup -Identity "<GroupName>" | Select DisplayName, ManagedByOutput:
DisplayName ManagedBy
----------- ---------
Group {}
In this case, the group has no assigned owners.
Why Does This Happen?
The Solution: Assigning Group Owners
Make sure to assign an owner to each of the Office 365 groups (mail-enabled and security groups)
First, assign a new member to the group using the Add-UnifiedGroupLinks cmdlet:
Add-UnifiedGroupLinks -Identity "<GroupName>" -LinkType Members -Links <UserEmail>Then, make the newly added member an owner of the group:
Add-UnifiedGroupLinks -Identity "<GroupName>" -LinkType Owners -Links <UserEmail>Once the ownership is added, verify the changes using:
Get-UnifiedGroup -Identity "<GroupName>" | Select DisplayName, ManagedByPreventative Measures
To avoid such warnings in the future:
Regular Audits: Periodically check for groups without owners using the following command:
Get-UnifiedGroup | Where-Object { -not $_.ManagedBy } | Select DisplayNameMonitor Backup Logs: Regularly review Veeam Backup reports to catch warnings early and address them proactively.
