if your using win 7 you can got to control panel> troubleshooting click "view all"on the left pane then select playing/burning dvd's option.
if that doesnt work go to device manager in CP and see if the drive is recognized if not select view hidden in the tool bar and see if there's options to fix it. If all that fails then maybe if you just installed it or re-installed your os the jumper is on the wrong pins.
good luck