Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Hii ,
Unfortunately, even if you manage to activate Office, you won't have access to all its features; specifically, you won't have the option to edit and save files within the Office suite.
Microsoft announced that, as of July 13, Office 365 no longer supports editing and saving functions on macOS, even if the minimum requirements are met.
https://support.microsoft.com/en-us/office/lifecycle/officeinstall/update-m365-office-macos-ios
To access all Office 365 features, you would need to meet the minimum requirements shown in the image below:
Regarding error 0x0, you need to completely uninstall Office and install the version compatible with your macOS—which would be version 16.77.
https://learn.microsoft.com/en-us/officeupdates/update-history-office-for-mac
Restart your system and sign in; please keep in mind that if you are using macOS Big Sur, you will not have editing and saving capabilities in Office 365.
Please consider rating the question (by accepting the answer or not) and visiting the Microsoft Q&A community if you have any further questions.
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