Had a similar problem once on XP so I followed the advise below to remove both the "upperfilters" and "lowerfilters" registry values:
Removed the CD-ROM software, uninstalled the drivers for both drives, rebooted and let the system reinstall the drives. No luck. I've also got almost 40,000 "Event 11, cdrom" errors in the event viewer. I verified that both drives are at the latest firmware release. One drive is a Plextor PX-716-A (SATA drive) and the other is a Lite-On SHM-165H6S (ATA). Both drives worked under XP and initially under Vista (at least for two days), so I don't think I have faulty drives or cables.