CD Drives not recognized

I know this is somewhat related to a bunch of posts already here, but I
could not find a post where a proposed solution had worked. Here's my
problem:

About two weeks ago, I upgraded to Windows XP. At that time, all the
hardware, including my CD-RW and CD-R drives were working properly. This
past weekend, I noticed that both of my CD drives were not working. I get a
Code 39 error in device manager. I have tried the hardware troubleshooter
solution and it does not work. I have also tried the following:

1. Downloading the CD-RW patch from Microsoft - installation not successful
2. Uninstalling the drives and rebooting the machine - here I get asked to
insert the XP CD, but it can't read it because XP is not recognizing the
drive. Using Win98, I copied the directory XP was looking to install from
over to another drive, but the intallation the next time XP started still
did not work.

Any thoughts? I have an Acer 1032a CD-RW and some generic brand CD-R.