The first thing to try: another keyboard. For a desktop, that's easy. For a laptop, try an external USB keyboard.
I need help, since last night, my keyboard type one wrong character. Instead of typing "r" it type either u or 4. I'm running a virus scan right now but for now nothing. And when I searched internet I can't find my p4oblem. I find more of multiple letters one wrong. And I can't keep on typing and using ctrl+v all the time. I did learned that alt-114 also a way to type r....

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