Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
For Office 2021 on Mac, error 0x0 is associated with an Office licensing issue.
Try this in order:
- Verify macOS version.
- Office on Mac should be running on at least macOS 12 or later.
- Close all Office apps.
- Update Office.
- Open Finder > Applications > Microsoft AutoUpdate.
- Select Update All.
- If Office was installed from the App Store, open App Store > Updates and update the Office apps there instead.
- Launch Word again and try activation.
- Open Launchpad > Microsoft Word.
- Select Get Started to begin activation.
- If activation still fails, confirm the correct licensed account is being used.
- Sign out and sign in again with the Microsoft account associated with the Office purchase.
- If needed, choose Sign in with another account.
- If Office still cannot activate, reset credentials.
- Open Spotlight and search for Keychain.
- Search for Office and delete the data license file.
- Then run the Microsoft 365 Activation troubleshooter from Get Help.
If the apps show as up to date but activation still fails, updating through Microsoft AutoUpdate or the App Store is the primary documented fix for the 0x0 / license issue on macOS.
- Unknown Error 0x0 or License not found error in Microsoft 365 or Office running on macOS | Microsoft Support
- [Activation](https://support.microsoft.com/microsoft-365-activation-licensing/what-to-try-if-you-can-t-install-or-activate-office-for-mac)
- [Office for Mac 2021](https://support.microsoft.com/office/lifecycle/officeinstall/download-and-install-or-reinstall-office-2021-office-2019-or-office-2016)