About 4 years ago, I instsalled Office 2010 on a client's computer. During the past 4 years there has not been a problem. A couple days ago, though, It said it needed to activate the key. Well, we tried and MS says it is an invalid key.
She did upgdrade to Windows 10 late in the free upgrade period, but I think that is the only significant change to this machine.
Anyone know how to solve this?