The PC this had Office 2010 installed and validated 14 months ago. Yesterday it asked for the Product Key.  This was input, but no programs will open.  The message says to repair through Control Panel.  After rebooting, it's the same.  Product Key is genuine.

I7 CPU

8Gb RAM

Win 8.1 64 bit.

Will it need uninstalling and reinstalling?

Hi,

I understand the current issue is that Office 2010 asks for Product Key, but I'm not sure what error message it prompts, could you please provide the complete error message in detail?

Or does it imply the Product Key is invalid?

For this kind of issue, we may try repairing Office from the Control Panel first, sometimes a reinstallation is also needed.

Regards,

Melon Chen
TechNet Community Su