Same problem here...
My dvd drive was perfect before installing Win7.. I had winXP, then W7 7100 RC, then W7 7600 RTM. My dvd drive worked fine within the first installation of W7 RC and during the next 2 month... then seemed to be broken or something because it disappeared from the file manager and from the system devices list... but, of course, was phsically ok because of the light and the spinning.
The problem is that it was not a defined issue, because sometimes the computer started with the dvd drive recognized just for a couple of minutes and then disapeared. This permitted me to look for a "lucky boot-up" (where the computer recognize the dvd drive) to try and reinstall the newer version of Win7 (7600).
I did it and the new configuration worked for a couple of hours. Then the dvd drive disappeared again.
I tryed the Upper/lower filters fix: useless.
I tryed the drivers integrity control fix: useless
I tryed to flash the bios of my pc wit the newest version: still useless
I have an Acer aspire 5520g with a 2 core AMD processor.
When Sarah said " I found this info in the registry: MAT****A DVD-RAM UJ-861H ATA Device" i figured out that UJ-861H is the same name if my dvd hard drive. Could it mean something?
I'm getting crazy like Sarah with this problem, I don't really think it is only a coincidence with the broke of the drive..
Any help will be appreciated, sorry for my english misstakes, I'm doing my best.
Cheers