Are you using the same CD reader on both? If not, try switching the readers and see if the problem moves. If it is an external drive and a usb device, make sure another device works in the port. A thumb drive is a good test since they do not normally need a driver. If it is an internal drive, make sure that the jumpers on both the hard drives and the cd reader are set the same. Also if internal get a replacement cable. I think that somewhere in this process you will be able to isolate the problem.