ive had a wireless keyborad for over a year and its been workingperfectly until now....

yesterday some kids came to our house ..little bros friend and the did something to the computer...and this is whats happening now..

the keyboard is not responding....when you press anything a beep comes from the motherboard (presumably) and it doesnt type..however if i keep my finger on the letter..it does it after about 5 secs....i dont get a keyboard error in the beginning when putting pc on...ive tried everything..connecting ..changing channel..ive even bought a new keyboard..but i still get the same error...the mouse works perfectly...the problem cant be with the keyboard..as i bought a new one just today and still get the same error..

plz help..i have quite a few coursworks to be completing..but without a keyboard i dont have much hope..