Neither PS/2 nor USB Mouse OR Keyboard will work

Hello,

I've been trying to troubleshoot this for days and can't really seem to get anywhere.

I have a Dell 4600C. I've always used a wireless mouse and keyboard (the same ones I bought with the system new 5 years ago)

The other day I shut the system down, unplugged it and then unhooked it to take it in the other room(I was spring cleaning and wanted to get the dust and stuff off the back of it).

I cleaned the back up up (As I've done a few times a year for the past 5 years) and then hooked it back up and turned it on. Everything seemed fine with the start up.. it took me to the "enter the password" screen and all seemed well.... except, my mouse and keyboard weren't working. The lights on the receiver, which is USB, were all on just fine and the lights on the mouse were on as well.. the keyboard doesn't have any lights. I shut down, rebooted, unhooked and did every combination of things I could and it still wouldn't work. I thought maybe the receiver and the devices weren't "talking" any more so I tried a PS/2 mouse and keyboard and those won't work either. I now know my wireless set is fine, because I am using it right now on my backup system, so it's something to do with the ports on the other system. It's really odd that the lights all work and the ports seem to generate power, but won't actually work.

Help!!!!! The system starts fine but I can't use it because mouses and keyboards won't work! Does this seem like a motherboard issue??? It's the only other thing I can think of.

Thanks!!

 

Pull out and reseat the drive cables. It should not really be a cause, but the cables getting knocked loose is what often happens.