Are you saying the task scheduler isn't firing off the event or is the event being launched, but not completing it's action? I'm not sure how to fix the task scheduler. There is probably a service to start/stop it. If the action isn't completing, have the task scheduler launch the program under the administrator's account or an account that has administrative access.
I monitored the scheduler, it says running, but nothing happens, as if it never started. There is another task the is scheduled and it runs normally.