We installed Admin Ad plugin about 1 week ago.
We added an Ad yesterday. Now the site admin menu is gone and site admin doesn't have permission to change users, delete blogs - everything to do with spam control.
We checked the user info and user1 is still admin for blog 1. Everything looks right.
We changed the name of both admin_ad and admin_message. Then we deleted them. The ad no longer appears at the top of the dashboard.
But - we still do not have the site admin menu - and site admin cannot change permissions, user info, etc.
This is the only change we've done.