I have a Compaq Deskpro EP/P550 with windows 2000 computer. That at one time I installed a DVD drive and a DVD burner in. I then took them out and put the cd drive back in that I got with the computer. And the CD rom does not work. I put my DVD Rom and DVD Burner back in the computer and it will not work. They open and close and the disk spins inside but nothing comes up on the screen. I troubleshooted them drives and it tells me the drives are working fine. But I did notice that when I go into my computer the only things in there is my hard Drive (C),my floppy drive (a) and my control panel. I must have somehow erased the files for my other two drives. And when I go to start, run and enter d: in I get an error message that the d: file is missing or has been removed. How do I get the drives back up there so that the computer reconizes them? My modem does not work on there right now because it needs to be installed and I can not install anything without my drives working. So basically all that I need to know is how can I get those two drives working again. Or should I say how can I get my computer to reconize them without being able to reinstall them? Please Help Me.