A little more info. would help people to give some areas to check or try..
I thought there was a post sometime ago about a similar problem, but I can't seem to find it anywhere.. I'm sure it entailed cleaning up the registry and possibly some other areas..
All programs report faults,exceptions in to the event viewer. Check the time and exact date when you experience this issue ,look in the event viewer under applications or system(depending on your OS) look for Red X's and an eventid will help determine the issue.