I have no clue what caused this, my son went to play a game and after putting the disk in the drive and using the shortcut to launch it, it said please put this disk in the drive. After looking this is what I found. I have 1 cd/dvd drive in the comp, the ND-3520a, the icon for it in my computer is all of a sudden missing. I went to device manager and it shows up but with an exclamation mark. I unistalled the driver then did a scan for hardware changes, it's recognized, but as the driver tries to install, it sais a problem occured during hardware installation. it reappears in device manager again but with an exclamation. I thought maybe something happened to the drive so I took my ND3550a out of my comp and put it in place of the other, same deal, it recognizes it as my 3550, but has an exclamation mark by it now. Switched cables incase it went bad, same deal. Booted in safe mode, still no drive. The one thing I can do is change the boot order and have it boot from my windows CD so I know somethings working, I just can't figure out what's not. Anyone have any clues what the heck is up..? I tried to google the problem but only got a couple good leads, none of which fit or fixed my issue. Device status sais "Windows cannot load the device driver for this hardware. The driver may be corrupted or missing. (Code 39)" I'm stumped.