This could be a bad motor, or lubrication needed where the motor meets the track.
Related story: I had rolled down all the windows a couple of days ago to get the stink of the PO out of my "new" car, and it was somewhat of a misty day. Well, the temps dropped below freezing and all that mist turned to ice. All of the windows froze completely open! I got one up by jiggling it and cracking the ice seal, but had to turn on the car and let the heater do its thing before the rest would come up.
