I've upgrade the controller 3750 from the version 188.8.131.52 to the version 4.1.181. After this upgrade few AP are not anymore associated to the controller and I receive the following message
Failed to authorize AP with Base Radio MAC 00:13:c3:4c:88:b7. Authorization entry does not exist in Controller's AP Authorization List.
The controller is in Master Controller Mode and I've all AP in the AP Policies