reinstall CDROM or CDRW

Dell Latitude notebook, PIII, 128MB, 20GB, Win2K. I replaced the working CDROM with a new CDRW, but it shows a yellow mark in device manager. When I put the CDROM back it also had a yellow mark. When I try to reinstall the driver there is a message that the registry is corrupted. Where do I edit the registry to reinstall the CDRW? What other options are there without formatting the hard drive?