I have a Dell XPS 400 running Windows XP Pro. It has 500 gb hard drive and 2 gb of memory. I recently formatted and reinstalled the OS because cdrom drive keeps disappearing. If I set the bios to boot from the cdrom it boots from the cdrom, however the cdrom is not accessible from Windows and in the device manager it is visible with the yellow exclamation mark. If I delete it and reinstall it the cdrom drive is reconized during the installation. Then it says there was a problem installing your hardware and it may not work correctly. So........... it is gone again and I do not want to reformat just to get the cdrom back...... can someone help me????