Unable to edit Office files on Mac

Symptom:

Upon opening a file using Office 356 you encounter the following error:

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Possible Solution:

1. Launch each Office app installed on your Mac, click on the application name (eg Word) menu and choose Sign Out.  Then quit the application.

2. In the Finder, click on the Go menu and choose Go to Folder

3. In the box, type: ~/Library (see screenshot below)

4. Click on the Group Containers folder

5. Locate the following three files/folders and drag them to the Trash

   1. UBF8T346G9.ms

   2. UBF8T346G9.Office

   3. UBF8T346G9.Office.OsfWebHost

6. Empty the Trash and launch an Office application to check if you can now edit documents.

7. If the warning bar from the beginning still appears and a "User other account" button is present on it, click that button and sign in with your CatID

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