i have tryed usb,seriel,ps2 no mouse will work was working fine till a few days ago its my sons pc and he went on the net with it and it has'nt worked since, os win me thanks for any replys

Have you tried;

Removing the mouse in Device Manager and rebooting?

Ensuring the appropriate port is enabled in the bios? (ie; Comm1, Comm2, PS2,etc.)

ive removed it and it still didnt work
and carnt get in to bios never known password

If this is a desktop system, and the password is set on the bios entry, clearing cmos should clear the password.

Physically disconnect the machine from power. (Unplug it.)

Remove the left side cover panel (or the tower enclosure if it's a one piece wrap-around). Carefully remove the cmos battery. (Do not bend or force any retaining clips etc. It's a silver disc like a big watch battery. See attached photo.)

Hit the power button and leave the machine sit for two or three minutes.

Snap the battery into it's holder. (PLUS (+) side is usually up.) Plug in the machine and boot. Hitting the appropriate key for your bios should get you into the setup screens/utilities. Your date and time may need resetting.

bios has been reset
windows can not find any mouse,

Yes, but did you actually go INTO BIOS and checking if the correct port is enabled like you should have done? Or did you go straight back into Windows?