Windows made my drives disappear??

I can't quite figure this one out. The other day I noticed that my cd-rom's had disappeared from My Computer in explorer, but had been working fine the day before. In Device Manager they both had the yellow exclaimation marks over them, so I uninstalled and reinstalled them and the exclaimations went away, but they still didn't appear in My Computer or in Manage Disk Drives. I tried booting from them and they worked fine in BIOS.

Next I tried loading Daemon Tools (program for mounting cd/dvd images as drives), but it wouldn't create any new drives. If I try to mount an image or "unmount all drives" it says "Unable to Mount (or Unmount) Drive. Device is Locked". Changing drive letter on it or on the harddrives didn't help, but removable drives (usb) work fine.

I've never had this happen before. Searching around on Google I found a few people who had the same problem, but never found a fix for it. Anyone know how to fix this?