I just read your post:
2 questions:
1) Is numlock enabled in BIOS? If so, disable it.
2) Do you have a saved session ( say, via Switch User, rather than having done a true log out)? If so, eliminate it.
I have experienced your situation before and the culprit has always been one of these 2 situations. Hopefully, yours has the same cause. Good luck!
oldschool