That's a good question in your post #121 yescool2002. Also why is possible to get systems reading again only to have it fail again when there's difficulty in reading a disk as shown in post #68? Dee-27 is likely right about the problem not easily being fixed. Also I think elwood_mb is on the right track to buy other brand drives which is exactly why I got 2 Pioneer 111D drives when I encountered problems with the NEC 3520 drive and why I'll not get another NEC unless this complex issue is resolved.