So right now I have 3 Atari 810 drives   2 have the door which pops opens and the other has the one described as a garage door.   One of them with the pop open door works but does not sound ideal. It does load software though. The second and third give Boot Error messages.   Question, what can i test? Could it be the belt / mechanism. One of the units came with a perfect 810 box so I am keen to get at least the top units with the pop open doors working.   Can these be saved, improved?