(no subject)

Question for those of you familiar with the new Microsoft Office:

Every time I try to type in Word or Excel, it tells me - and I quote - "This modification is not allowed because selection is locked." I can't type. This could be bad. So what's locked? What did I do, and what can I do to fix it?

I'm reasonably sure numbers lock is not the problem, as I already fiddled with it.