I haven't made any changes but I just used ctrl-alt-del to bring up the task manager and it didn't come up just :
lock this computer
That's all that comes up on the screen
Windows 7 home edition 64 bit
It worked fine just a few days ago.
Got it working again. Had to do a sys restore to a week ago. Also ctrl-shift-esc works again too. A little strange, but the only things that system restore showed being recently installed was a few critical updates. So I guess I'll just have to wait till Tuesday to see if it messes up again......sigh