I have an optiplex 745 that in Device Manager the CD/DVD drive (HL-DT-ST DVD+-RW GSA-H31N), "is working". I have reloaded the dvd drivers, I have deleted the dvd drive and rebooted to restore the dvd drive, I have downloaded the firmware and burned to the dvd drive. I have even deleted the lower filters in the registry trying to get this drive to work. I need to re-OS this computer and without the DVD drive, it makes that difficult since the 745 came with cd's to restore and reload windows xp. I have done a repair on the system by copying the Reinstallation CD onto a USB drive and repairing Windows but still cannot get the DVD/CD drive to read or recognize any software media installed into drive. Any help would be appreciated. My next step is to try taking another drive from another of these machines at the office and seeing if the drive itself is defective, but I don't believe that is the case since on one occasion I thought I had it working and it recognized a software media I inserted, but after the reboot it no longer worked.
jkuss, aside from reseating both ends of the data cable, if that fails then your plan to try another drive would be my next step. Drive failure is certainly not unheard of, although it is not terribly common. I think you're on the right track, after all the items you have tried, all of which were good moves.