I have a Dell Dimension 4550 desktop. My CD drives stopped working. Nothing happens when I put disks in. When I click on the D drive it still says “not accessible”. I was advised to replace the cable to the drives. Now when I click on the D drive I just get the little hourglass icon. I wait and nothing happens. When I closed the window the icons were gone from the desktop. I had to hit the power button to shut down my PC.

Looks like you need a new one.

It definitely sounds like your CD drive has gone bad. if you want to make certain then unistall the IDE channel the drive is on in device manager and reboot. if windows does not install the drive on bootup then you know the device is bad,

Yep you probably need a new one. Cables don't usually go out but drives sometimes do. You can test and see if you have a software conflict by booting into your Windows or reinstall disk during the boot process.

Go into your BIOS and make sure the first boot drive is your CD and put your Windows disk into the drive. Save the BIOS change if any, and boot your computer. If you're not asked if you want to boot into the Windows disk then your drive is broken. If you are asked if you want to boot into the Windows then you probably have a software (driver) conflict somewhere.

I don't know that much about computers but I question whether the disk drives are broken. Is it likely both of them would stop working (I have two)?

I don't exactly understand your instructions. I don't know much about fooling with computers.

In BIOS, is the first boot drive the one that says:
"Secondary Drive0...Cd Rom Readers"?

I don't know what my Window disk is. I have disks from Dell for things like support and Internet software and device drivers.

When you get into your BIOS you will probably see the word BOOT at the top of your screen. You should highlight the word and then push the down arrow or push the enter key to get into the menu. You'll probably see floppy listed first and then your hard drive then your CD rom. You want to make sure that your CD rom is listed before your hard drive. Now save the changes and put your Dell recovery disk into the drive and boot your computer. The recovery disk contains a copy of your operating system or Windows. Your computer should ask you if you want to boot into the recovery disk. You don't actually want to boot into the disk you just want it to ask you if you do want to boot into the disk. If it does ask then your drive is probably fime and you have some sort of software conflict. If it doesn't ask then your drive is broken.

have you added any drives to the computer recently?