How can I get Home Office and Student (2021) to work an a Mac after a minor system update

Will Hew 0 Reputation points
2026-08-28T18:34:51.7266667+00:00

My Mac system was updated (OS Ventura). Now Home Office and Student (2021) will no longer open. Can I remove the license and then reinstall it or uninstall it (how?) and then reinstall it?

Thanks for any assistance ...

NB

Microsoft 365 and Office | Install, redeem, activate | Other | MacOS
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  1. EmilyS726 267K Reputation points Independent Advisor
    2026-08-28T19:14:45.98+00:00

    Office program can run on macOS Ventura 13 only by using an older Office version.

    Microsoft ended support for Ventura with Office version 16.101, released in September 2025.

    Uninstall your current Office apps, then downgrade to version 16.101 by using this installer. 

    https://officecdn.microsoft.com/pr/C1297A47-86C4-4C1F-97FA-950631F94777/MacAutoupdate/Microsoft_365_and_Office_16.101.25091314_Installer.pkg?apid=ets

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  2. AI answer

    2026-08-28T18:35:07.1133333+00:00

    Yes. On a Mac, removing the Office license files and then reinstalling Office is a supported path, especially after an update when Office 2021 no longer opens or activates correctly.

    Recommended order:

    1. Remove the Office license files
      • Download and run the Microsoft license removal tool.
      • Open the .pkg file from Downloads.
      • If macOS shows an "unidentified developer" warning, hold Control and click the file, then choose Open.
      • Select Continue and complete the setup wizard.
      • When prompted, select Install to remove the licenses.
      • After it finishes, select Close.
    2. Open an Office app and sign in again
      • Open Word, Excel, or another Office app.
      • Sign in with the Microsoft account associated with the Office Home & Student 2021 for Mac purchase.
      • Restart the Mac after activation.
    3. If Office still will not open or activate, uninstall and reinstall the apps
      • Close Word, Excel, PowerPoint, and Outlook.
      • Open Finder > Applications.
      • Locate the Office apps, Control-click each one, and choose Move to Trash.
      • Reinstall Office from the installer for the version in use.
    4. Important Mac App Store note
      • If the apps were installed from the Mac App Store, those versions require a Microsoft 365 subscription and do not support a one-time Office Home & Student license.
      • In that case, remove the App Store versions and reinstall Office directly from Microsoft.
    5. If the issue started after a recent update and shows license errors such as "Unknown Error 0x0" or "License Not Found"
      • Make sure macOS is version 12 or higher.
      • Close all Office apps.
      • Open Finder > Applications > Microsoft AutoUpdate.
      • Select Update All or update the Office apps individually.
      • Then launch Office again and test.

    Caution: before removing licenses, confirm the Microsoft account that owns the Office 2021 license so the correct account is used during reactivation.

    AI-generated content may be incorrect. Read our transparency notes for more information.

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