We installed a new garage door opener 2 months ago (the tracks were already in place.. installed in early 06 when home was built). When I open or close the door, the top roller falls out of the track. What would cause this to happen. It has been working fine until about 2 weeks ago. It was slipping out every few days, now its every time :(

If the roller shaft is long enough, take the shaft with you to a hardware store and get one or two "Grip Clips" to go around the shaft and hold it in place.