I had installed Norton Personal Firewall and after that my cdrom, dvdrom and A drives didn't operate. Message: Inaccessible, function error. I uninstalled the firewall, uninstalled the devices and their drivers. After reinstallation, they still do not work. I am afraid to reformat as the A drive doesn't read. Both the cdrom and dvdrom will play audio disks and the LiteOn will record disks using Nero. Help!!