Windows cannot load the device drivers for this hardware???

Right off the bat I have to say I don't know much about computers but I am learning as I go. I am also having CD problems, but it seems to have something to do with the drivers. I have XP Prof with a CD/RW/DVD and CD ROM.

In the device manager both the CD/RW/DVD and CD ROM have exclamations in a yellow circle next to each. After I run the troubleshooter it tells me Windows cannot load the device drivers for this hardware. The driver may be corrupted or missing [Code 39]. Both CD hardware is connected to one cable.

I somehow caused this to happen by installing an A drive. Right after I did that the trouble started. I put everything back just as it was before. The cables can only be installed one way. I checked everything, even to make sure the pins weren't damaged. If they had made the wires route differently, you wouldn't have to take the computer apart to install a new device.

I have unistalled the drivers and let the computer find them about 15 times now and nothing changes. I tried updating the drivers to no avail. I checked the slave master jumpers and they are as should be. When I put a CD in the player it lights up and whirs like it is trying to work, and then nothing happens. Sometimes after uninstalling the drivers and then start the computer up it will have a little note at the bottom of the screen that says the computer has found some new hardware and then it goes away. When I go into the device manager and install the drivers again, both players still have the exclamation point.

I have no way of knowing if the drivers can be replaced or repaired, or if it isn't something other than the drivers. This is such a mystery because no action tried seems to help. The troubleshooter is about useless except for minor problems.

I could sure use some advice on what else I may try.