Symptoms:
1) The error MS Word 2021 throws is: You can’t make this change because the selection is locked
2) You are unable to edit any Word files, even ones you created.
3) The only application affected is Word. Other Office 2021 apps (Outlook, Excel, Powerpoint) and their functionality are not locked out and behave as expected.
Solution from IS&T:
In order to (re)activate the Microsoft Office license, you will need to follow the steps below:
1) Please ensure you are connected to MIT Secure (Global Protect VPN if at home) and uninstall all Microsoft Office products (word, powerpoint, excel, outlook. etc.)
2) Once all apps are uninstalled use the link below to download and run the Mac License removal tool so IS&T can reset your license with the Office products.
https://support.microsoft.com/en-us/office/how-to-remove-office-license-files-on-a-mac-b032c0f6-a431-4dad-83a9-6b727c03b193
3) Once the license removal tool has ran, please go to office.com and sign into your MIT account.
4) Install Office 2021 back on your Mac. Remember to run the installer first and then the serializer.
5) Once Office 2021 is reinstalled, you should be able to open word and activate and sign into your MIT account there.