You left out so much information, it will be difficult to help and from your vague description, I don't know where to start helping you. Let start with the basic stuff first.
1: Is the drive listed in My Computer and Device Manager?
2: Has it ever worked before?
3: What did you do that made it stop working?
4: Have you made any hardware or software changes?
5: Is this the only optical drive installed in the system?
6: How is the drive configured and what ide port is it connected to?
If your drive is not listed in My Computer then you may need to perform the "delete upper and lower filters fix".
Please read post #24 in this thread:
http://forums.driverguide.com/showth...t=21669&page=4
It contains instructions on the
delete the upper and lower filters fix
Also, there is a STICKY posted in this forum that contains a file from Microsoft and instructions that will do this registry edit automatically instead of having to do it manually.
And here's another method that will do this automatically for you if you're afraid to edit the registry manually.
And it's possible you have a defective drive as UJ-xxxx models are notorious for going bad. I've seen new one's fail the first hour of use.