after xp upgrade, no keyboard function

I upgrade to xp home. Keyboard was fine before. I have
tried an alternate keyboard. Kboard functions in bios.
Drivers will not load . Control panel kboard icon shows no
drivers,therefor there are no properties and i can not
change or load a new driver. I can not do a xp repair
install because I need the keyboard function to in put the
reg number. Sys info/input devices shows the word keyboard
but the info window is blank. Driver files are in the
sys32/drivers folder(i8042prt.sys & kbclass.sys) I have
tried find new hardware, add new hardware ..ect. If I can
not fix this problem I will have to revert back to me,
which i do not want to do. Any help you can give me would
be great. My keyboard is a standard ps2 101-102
thanks
ToddG