hi there...i have NO clue about laptops....i can do basic stuff but nothing major...my friend who suposidly knew about laptops helped me get rid of a virus...but a week later i have realised he has uninstalled something i need...as i have no sound?!?!? it just says no audio device found...it then said new hardware found...so i tried to install it but it says it cant find the information needed....please help me?!?!?!?!