DVD/CD Drive(s) not working!

System: Windows XP

Issue: My DVD drives stopped working! They showed up in Device Manager, but with a yellow exclamation mark on them. Windows said the drivers could not be loaded for them. It gave me this message:
"Windows cannot load the device driver for this hardware. The driver may be corrupted or missing. (Code 39)."


I had to change two registry keys.

I went to here:


And then cleared out the information for the keys "UpperFilters" and "LowerFilters". You should be able to just delete the UpperFilters and LowerFilters keys.

Cause: Not sure. I believe I uninstalled some Virtual CD software (such as Alcohol 120% or Daemon Tools), and Windows threw a fit.