Office Applications Prompting for Password
If you change your MS365 password and MS Office prompts for your password and will not accept go thru the following steps.
Click “File”
Click “Account”
Select “Sign Out”
Select “Yes” at the pop-up window.
Close the application
Re-Open the application and re-enter your credentials.
Click “File”
Click “Account” at the bottom left of the page.
Click “Sign In” and authenticate with your email address and password when prompted.