Mike, I know it's been over two years, but your comment was just what we needed to solve our problem and had previously been having awful search luck! Thank you kindly!
@It-Works This worked for me as well. I wonder if it may be that owners don't automatically have the mailbox show up in their Outlook by design. Perhaps the system is trying to accommodate someone who may be an administrator who is creating groups but doesn't necessarily want to see all the emails. This gives you the option of doing so by also becoming a member as well as an owner.
