Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Hi, Teija Norvanto
Please try the following options:
- Close all office applications (make sure that office applications in the background are also closed).
- Update your MAC system to the latest. Update macOS on Mac - Apple Support Disclaimer: Microsoft does not provide any warranties and/or guarantees, implied or otherwise, and is not responsible for the information you obtain from third-party linked websites or for any technology-related support.
- Follow the steps in Connections to clear the office key. How to remove Office license files on a Mac - Microsoft Support
- Re-open the office app to see if you can activate it successfully.
I hope the above information can help you. Feel free to send a message if you need further help.
Best wishes
Aiden.C - MSFT |Microsoft Community Support Specialist