Only backspace works on startup

Open a command prompt. Type the whole alphabet. None of them work? Which ones do work?
Or can't you logon in windows at all?

Featureless said:

I had noticed that while i was playing a game that my escape key was not working inside of the game. I found this odd so I exited the game and opened google chrome. After doing so I realized the other keys on my keyboard were not working as well. I decided to restart my computer to see if that would fix the issue. When my computer loads up the only key that responds is the backspace key, and it just seems to enter a random letter into my password for my login. I tried using a different keyboard and booting into safe mode but neither worked. Any ideas how to solve this issue?

F8 on boot to enter safe mode doesn't work as well? It did before? Can you enter BIOS?

Featureless said:

I can enter safe mode, but it still requires me to enter a password for my account, which I can't do

So F8 on boot work?! I thougth none of the keys (except backspace) did work(?)

Press F8 on boot. Now select "repair my computer". follow instructions. Can you enter password there? If so click "command prompt" on this screen. Does keyboard work now?

What keyboard layout do you select after "repair your computer"? (first screen after that)
On normal logon screen it's as well selectable. Click keyboard icon in top left of screen

You tried another keyboard as well... both were ps2 keyboards or usb?