How do I activate Version 16.66 on my Mac OS Catalina computer?

Maria Constantin 0 Reputation points
2026-07-31T19:35:42.3433333+00:00

I purchased Microsoft Office, but unfortunately, one of my computers does not support the updated version. How can I activate Version 16.66 on one of my computers? I tried installing version 16.66, but I still cannot edit Word files.

Microsoft 365 and Office | Word | For home | MacOS
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  1. EmilyS726 256.2K Reputation points Independent Advisor
    2026-07-31T20:10:09.19+00:00

    Hello,

    If your OS is above version 12 but below 14, your office products can be functional, but Microsoft no longer maintains or updates that version. In this scenario, you can install the older downgraded version.

    However, if your macOS is below 12, Office products will now enter reduced functionality mode. In other words, the OS is too old to receive the licensing update the Office now requires. Downgrading to version 16.66 is not going to help resolve this issue either. The downgrade option is only for macOS between 12 and 14. Sorry

    This is an update that occured on July 13th and Microsoft shared it here: https://support.microsoft.com/office/update-microsoft-365-or-office-on-your-macos-or-ios-device-f418ae5d-bb5f-4078-b3d9-9340f5dd084e?apid=ets

    If your device cannot update its OS to at least 12, your options will be: Use the web version or an alternative like LibreOffice. And you want to cancel your subscriptions.

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  2. John Korchok 235.3K Reputation points Volunteer Moderator
    2026-07-31T20:25:23.9033333+00:00

    Microsoft is abandoning users of older Macs. As alternatives to Office for Mac under Big Sur, you can use Word for the web or Google Docs. For desktop software, take a look at open-source LibreOffice, which has good compatibility with Office file formats.

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