Playing with children's Dell 486/66 and probably caused usual mayhem! Had upgraded to 8x CD player a month ago, always a bit tempremental (the CD not me) but last night accidently deleted through Add/Remove, TewakUI. Now, and probably totally unrelated, CD has given up the ghost. Device Manager sees it okay as Toshiba and power supply ok. But, nothing will read off it and although CD start up light powers up, nothing further. Explorer shows D:\ as not accesible and The device is not ready.
Refastened cables, tightened everything I can reach internally and no luck.
Reason for mentioning TweakUI above is that I've convinced myself that the last thing I was looking at before causing the problem was the CD section in Tweak and Autorun.