My Dimension 4600 is almost a year old (I've got about a month left on warranty) so I need to address this problem now after living with it for several months.

 

Every now and then my CDR and DVD drives will disappear.  I will go to open one to insert a disk and they won't open, and they aren't listed under My Computer.  If I reboot, there they are and they will work.  However, they will eventually disappear again.  They were fine until about three or four months ago.  I tend to think it isn't a bad drive as they both do it and both started doing it at the same time.

 

There is something on the Dell support knowledge base, but it appears to be a shotgun approach and a bit too technical for my level of understanding.  To compound the problem, one of the things to try is to creat a diagnostic floppy disk, but my floppy drive also does not work, but I don't think it has worked since I got the system -- I didn't even think to try the floppy until I'd had it about 6 months  -- every floppy disk, even ones I know are good and work on other computers, result in a "disk is not formatted" message.  If I try to fomat a disk, I get an error message that it can't be done, yada-yada-yada.