Code 41 keyboard problem

Yesterday someone came out and connected my computer to my home network. After they left and I got back to my computer, I found that my keyboard didn’t work. I found that in the device manage my keyboard's icon had an exclamation point next to it, and when I clicked on it it said:"Windows successfully loaded the device driver for this hardware but cannot find the hardware device. (Code 41)". I assumed there was something wrong with my ps2 port, so I went out and bought a usb keyboard. No luck. So far I have tried: removing the driver and reinstalling it, removing the driver, unplugging the keyboard, plugging it in and installing the driver, removing the driver in safe mode (which I can access by the way; the keyboard stops working when the computer starts up.), trying different keyboards, and even removing SP2 (that solved someone on a different forum's problems), and nothings worked so far. I've also tried system restore, but I don’t know for sure if it restored my computer to a time earlier than when it was messed with. The person who connected me to the network is on vacation now, so I cant really contact them. I've scoured the internet (using the onscreen keyboard... yay...), and can't find anything helpful.

 

umm aparently i cant edit my message, but just as a note I wasn't sure where to put this. so if its in error please don't hesitate to move it/flame me.

 

also i forgot to mention that the buttons on the top of the keyboard work. (buttons specific to the keyboard like media, favorites, volume etc)