DVD Writer and CD Drive stopped working (Code 37)

Running Vista RTM for a week. Now both of my DVD/CD drives are no longer
showing up as drives in Windows explorer. In device manager they both show
with a Yellow ! sign and the status message "Windows cannot initialize the
device driver for this hardware. (Code 37)". I have tried uninstalling the
drivers and searching for new drivers. Each time I get the same results.

I ran the "Check for solution" optons and submitted data to MS but no reply
so far.

I used these drives during the first few days after installing Vista RTM to
install other software without any problems. I do not know at what point
they cease to exist.