Booted my old Win 10 desktop as normal this morning, but can't log in. The keyboard and mouse are alive, and Windows recognises that a key-press has been made, but it's not showing on the screen, and the cursor doesn't advance. So, I can get the log-in box, but can't type anything in it! I can't boot to safe mode because it doesn't recognise the shift key. Is there another way to get in? 
