A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
If this problem is affecting all Office apps, and that 'Repair Now' button is not resolving the problem, the best option is to to perform a full repair of your Office installation.
Open the Settings App (gear icon on your Start Menu)
Go to Apps, then scroll down to find Microsoft Office
Select that and choose Modify - Online Repair.
That should fix any issues with your Office Installation