Only the wide cable needs to be unplugged. My dad's machine did the same and the drive door would not open. Why? The drive had failed. Being on the same cable it knocked the other drive out too.
I have a IBM clone with about 16G of free space. I am using Windows XP 2nd edition. I have a generic CD Rom and a Sony CD ROM R-RW. At the same time both drive numbers began disappearing from my computer. They also were not recognized in my BIOS. If I reboot they appear in my BIOS but promptly disappear when I try to use them. The generic tray will open but will not function and the Sony tray won't even open. I opened the tower and everything appears to be hooked up properly. What else can I do?