I have a 3 month old computer (Dell Optiplex 360) and a new DVD writer ( Memorex - MRX-550L v1) that was bought at the same time. One day last week The DVD was not seen in My Computer, but was seen in control manager with a yellow explaination point. I uninstalled and rebooted several times and with no changes. I then removed DVD and hooked it up to another computer via a USB connection. The DVD works flawlessly, I believe I either have a hardware problem (bad SATA cable or socket) or a software problem. Which (or something else) do you think it might be? Thanks for any suggestions.