Thanks Thomas for the suggestions! I'm resorting to opening the door manually for now, so the rollers and tracks seem to be o.k. In looking at the opener itself, it appears that the mechanism/gear/sprocket? that moves the chain doesn't rotate anymore even though you can hear the motor running. Could it be that something is worn out?? If so, is it better to get it fixed or to buy another opener?? Thanks again for the help.