I have four drives hooked up on my computer - my primary 80gb IBM Deskstar hard drive, a secondary 20gb hard drive, and two CD drives -
a Pioneer 115 DVD-ROM and an ancient Acer CD/RW running at 4x read and 2x write.

In addition to this, I am running the latest version of Daemon Tools, a program that loads CD-images on my hard drive as phantom CD drives that act like actual additional CD drives.

For a long time, this setup worked fine.

But recently, whenever I perform a function that requires the computer to scan the drives (examples range from running a game that loads data from a Daemon-Tools phantom drive to simply picking a folder to unzip a file to by using the browse button in Winzip or any dialog box), whatever process is performing that function will hang.

It will hang and not close, regardless of repeated Task manager commands to close it. The only way to end it is to reboot the computer using the reset button.

Upon reboot, the computer will not detect any CD-ROM drives during POST, and I have to shut the computer off completely with the off button and then turn it back on for it to redetect the drives.

This problem briefly worsened by not detecting my primary 80gb hard drive, but I fixed it removing all drives except the primary drive. I then took out the Acer CD/RW since I thought maybe some compatibility problem might arise as it was really old.

No dice, since the problems keep occuring, seemingly at random.

Sometimes I get the blue screen of death with an error message that says "KERNEL_DATA_INPAGE_ERROR" "ATAPI.SYS". I flashed my BIOS to the most recent version; no dice either.

Please someone help me out.

System specs:
AMD Athlon XP 2100+
512mb PC2700 SDRAM
PNY GeForce4 Ti4600
Turtle Beach Santa Cruz
Pioneer DVD-115
Acer CD/RW 4x/2x
IBM Deskstar 120GXP hard drive @ 80gb
Maxtor 20gb hard drive
Windows XP Professional /w SP1

4 drives, a GF4600, an AMD 2100+ and how many case fans on what size power supply?

This (http://www.microsoft.com/technet/treeview/default.asp?url=/technet/prodtechnol/winxppro/reskit/prmd_stp_fvlq.asp) MS article may be of some help....

Also go through your system logs and see if you can find any other errors.

It's a 431w Enermax power supply. There are at least 5 case fans in the sizeable Chieftec case and the case temperature sits at around 50 degrees C during routine operation.

However I must add that the blue stop screen has occurred only twice. While it's pretty plain that it's connected to the drive problem, what is much more frequent and bothersome is the system hanging whenever it's told to access the CD drive.

I have now noticed that whenever this happens, the CD-rom will not open, like it has no power or something. This persists until the computer is TURNED OFF and then turned back on - reseting has no effect.

Any application that tries to access the drive in this state simply hangs and can't be terminated, period, meaning Windows won't shut off and that a forced reboot using the reset key is the only way to get rid of it.

I suspected that it might be old firmware. So I downloaded the latest firmware version from the Pioneer website (v1.33a) and tried to run it. It claimed that it did not detect a CD-Rom drive, and at this point the drive was still working, and not in its mysterious "no power and won't open tray mode."

It all makes me want to kick the computer. Repeatedly.

Try disconnecting the CD drive and see if the problem continues.....if it disappears then time to look for a replacement.