Do you by any chance have a cat?
I have a keyboard I used to use it would completely screw up and it wouldn't let me use keys that I needed to use for programming, I had to uninstall the driver for it, the crappy software that came with it, and find a deeply nested folder somewhere in the UserData folder for more junk the software wouldn't uninstall, and only then replugging the keyboard in would get it to work properly again... until it kept repeating the same thing and I went back to my trusted Logitech K120.