Im not really understand,Can u explain clearly?Updated keyboard BIOS with incorrect one.
Fault in keyboard BIOS.
Incorrect keyboard driver.
Removed keys to clean the keyboard and replaced them incorrectly.
Removed entire keypad to access laptop motherboard from above and replaced it incorrectly. i.e. not fully inserted.
Remember, laptop keyboards are a bit different from your average desktop keyboard and may offer specialized functions like media keys which may require the keyboard to have its own separate BIOS or a specialized driver.
I was just listing some possible causes of the problem.Im not really understand,Can u explain clearly?
+1 to this idea.You could try booting into a Live Linux CD. Because if it works fine in Linux then you know it's a windows problem.