I have a Windows 10 laptop with Office 2016 and Project 2010 and Visio 2010. The Project and Visio 2010 programs were installed full from CDs and have been working successfully with their valid/activated product keys. Yesterday, my user tried to open both programs and received messages that the Product key needed to change and he only has 2 days until it expires. I've run an Office repair on both programs and re-entered their product keys. Same message/same issue.
I don't see any Windows updates that were installed in the past couple of days and I'm not sure what happened or where else to troubleshoot.