Did you ever experience a time when your client just kept running an advertisement over and over again. This can happen when the client is a unable to properly communicate with the Managment Point. The client sends the "I completed the install" to the MP but it never get there. The client has a policy that says install once a day at 10am. Since the MP is not contacted the policy is still in affect and the MP has no way of knowing that client has completed and the client can't stop running the advertisement.
I have seen this when a move of the old MP to a new MP and the clients haven't automatically moved over. It has also happend when the client can't contact theMP correctly. This can also happen if someone places their boundary over yours. The the MP communication is disrupted.
A solution involves fixing the MP or re-installing the client.