I updated my Fedora 16 installation to Fedora 17 on Saturday, and the update worked without reporting any errors. I carried on working on the machine in question and then switched the computer off.
Last night I went back on the computer, I switched it on and got to the log in screen. At this point I tried to type in my password but the keyboard wouldn't work. I unplugged it (it's a PS/2 keyboard) and plugged it back in. The lights flashed for a split second but the keyboard still wouldn't work. I then plugged the keybaord in to a USB to PS/2 adapter, and the keyboard still wouldn't work.
I restarted the computer and tried to access the BIOS and I was able to do so. So the keyboard doesn't seem to be faulty, it just doesn't work when Fedora boots in to the GUI interface.
I did try to boot in to the "recovery mode" of Fedora, and the keyboard works here with no problem.
As I still have access to Fedora via a terminal interface, is there anything I can do to fix the keyboard problem via the terminal without having to reinstall Fedora?