DVD drives have vanished

[IllinoisWayne]

I am trying to troubleshoot a friend's computer (I built it for him a couple years ago).  His two DVD drives have disappeared from My Computer.  The last time he used one of the drives was to load a file import utility for Outlook from the Windows XP CD about a week ago (it is running Service Pack 2).  This is the first time since then that he has needed to use one of his DVD drives.

Now, when you look at Device Manager, it does not show there is anything under the "CVC/CD-ROM drives" heading.  However, under the IDE ATA/ATAPI controllers, there are two entries for Primary IDE Channel and two for Secondary IDE Channel (I presume because both can support two drives).  All four of these entries show a yellow circle with a black exclamation mark. 

I'm not sure what to try to resolve this without screwing things up any more than they are now.  Any help would be appreciated.

Thanks.

[Carbon Dudeoxide]

Try this.
Go to Device Manager, click a "+" sign next to IDE ATA/ATAPI Controllers.
You'll see two items:
- ATA Channel0 (or Primary Channel)
- ATA Channel1 (or Secondary Channel)
Right click on each of them, and click Uninstal. Confirm.
Restart Windows. They'll be automatically reinstalled.