My CD/DVD drive has disappeared - not shown in Explorer or Device Manager.

After Googling, I tried the Lower/Upper Filters Registry trick even though that only seems to work if the CD Drive is still showing in Device Manager with a Yellow exlamation mark. No joy.

I reset the BIOS to factory defaults and that made the CD/DVD drive reappear. Fantastic. But then the next time I booted up, the drive had disappeared again and the BIOS factory default trick won't work anymore.

It's a DELL Inspiron 6400 laptop. Any advice appreciated.

Dells are known for having parts short out, which is why I strongly recommend that anyone who has a Dell machine keep up-to-date with their warranty extensions. If you have a warranty, then get the CD-ROM drive replaced, as it sounds like you've tried everything from a user point of view.

The only other things I can think of trying is upgrading the firmware. Still, it should be recognized.

Myke, thanks. Electrical is possible, I suppose, especially because today it's reappeared without me doing anything except boot up. Got to go out now, but later I think I'll try updating the drivers while it's there. Thanks again.