The same thing just started happening to me. I can't figure it out either.
I don't have my recover disk. I've tried going back to the last known good logon, but no luck. Also I went to my device manager when I first got the error because I too lost sound and according to the device folder I have no devices.
Is this a virus, norton doesn't detect anything.
I also went in to my system config folder & noticed that alot of programs that I need to run when the computer is turned on, They aren't running. They show the status as stopped. I reset norton so the virus program will activate but everytime I close the folder and then reopen all the area's I had just clicked on are shaded out again.
Do you have any advice spare?
Thanks for any assistance you can provide.