A random thought.
Control Panel > AutoPlay Check "Use AutoPlay for all media and devices" on top if not checked. Problem resolved?
If not try to restore your system to a point well back in time when your device was functioning as it should. ( Of course I am assuming that System Restore is functional on your system. And of course you have to reinstall all programs you installed after that time, not to mention that one such program could have derailed the auto play or whatever else.