On Exchange 2010 organization, Is a user complained he or she can’t add/remove an member to the group they own? Are they getting this error message:
“Change to the public group membership cannot be saved. You do not have sufficient permission to perform this operation on this object.”
You double checked the group ownership permission is correct. As a admin you are able to add/remove members. But not the user.
You as a admin tried to open the group in Exchange Management Console, you get this error message.
“Couldn’t find object “username”. Please make sure that it was spelled correctly or specify a different object. Reason: The recipient <username> isn’t the expected type.”
Check two possible solutions:
1. The issue is disabled mailbox is stuck in the group. I would recommend use Exchange Management Shell to display the distribution group members (Get-DistributionGroupMember –identity GroupName). If you get an error for any member(s ), fix the member (remove the user, find why the user account is an issue).
2. Convert the group to Universal Group if not already.
One of the above fixed my issue.