KB #1004: "Failed to find group owner account"/" Cannot protect a group mailbox because the group does not have an owner."

Challenge

Backup jobs with Exchange items may output one of the two warnings:

"Failed to find group owner account"

"Cannot protect a group mailbox because the group does not have an owner."

Assign a owner to the group in question. Click here to find a guide on how to assign a new owner to an orphaned group.

Impersonation is not possible, as long as the Microsoft 365 group does not have an owner.