Office 365 no longer works on my Mac.

Question

Office 365 no longer works on my Mac.

Andriy Havryliv 20

I've had an Office 365 subscription for over 10 years. But, because I use High Sierra (I can't upgrade) none of my Office apps work anymore... That is, since yesterday. Can I download a standalone version of Office 2016 that is usable with High Sierra?

Andriy Havryliv 20 Reputation points

2026-10-28T12:41:42.7933333+00:00

AI bot replied:

A Microsoft 365 subscription does not include a separate perpetual Office 2016 license, but an older subscription build—Office for Mac 16.43—is reported as the last release compatible with macOS High Sierra 10.13.6 [---]

I have done this. When I sign in using my Microsoft account associated with the active subscription, the screen freezes. None of the three apps I use... Word, Excel and Outlook, can get past the sign in dialog box.
Stefan Blom 357.1K Reputation points MVP Volunteer Moderator

2026-10-28T14:47:02.9733333+00:00

You can reject the AI-generated reply from "AI answer," if you wish.

Answer accepted by question author

EmilyS726 277.8K Independent Advisor

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, which is your scenario, 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. In this scenario, downloading an older version unfortunately will not help.

This is an update that occurred 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.

I am sorry.

Andriy Havryliv 20 Reputation points

2026-10-28T14:20:36.4+00:00

Thank you very much for your response!

1 additional answer

Your answer

Andriy Havryliv 20 Reputation points

2026-10-28T12:41:42.7933333+00:00

AI bot replied:

A Microsoft 365 subscription does not include a separate perpetual Office 2016 license, but an older subscription build—Office for Mac 16.43—is reported as the last release compatible with macOS High Sierra 10.13.6 [---]

I have done this. When I sign in using my Microsoft account associated with the active subscription, the screen freezes. None of the three apps I use... Word, Excel and Outlook, can get past the sign in dialog box.
Stefan Blom 357.1K Reputation points MVP Volunteer Moderator

2026-10-28T14:47:02.9733333+00:00

You can reject the AI-generated reply from "AI answer," if you wish.
Andriy Havryliv 20 Reputation points

2026-10-28T14:20:36.4+00:00

Thank you very much for your response!

Answer 1

A Microsoft 365 subscription does not include a separate perpetual Office 2016 license, but an older subscription build—Office for Mac 16.43—is reported as the last release compatible with macOS High Sierra 10.13.6.^1^

Safest route for the existing subscription

Do not remove the currently installed applications yet.
Open an Office application and select app name > About app name—for example, Word > About Word—and record the installed version.
Obtain an Office for Mac 16.43 full installer from a Microsoft-hosted source before deleting anything.
- Microsoft’s update-history page confirms the Office release history, but its current download table provides links only for recent releases; it may no longer offer a downloadable 16.43 installer.^2^
- If an official 16.43 installer is unavailable, contact Microsoft Support and request the legacy Microsoft 365 installer compatible with macOS High Sierra 10.13.6. Do not use unverified third-party download sites.
After securing the installer, back up important documents and any locally stored Outlook data.
Remove the newer, incompatible Office applications from Finder > Applications, install 16.43, and sign in using the Microsoft account associated with the active subscription.
Confirm the installed release under Word > About Word. Activation remains dependent on the subscription entitlement and Microsoft’s legacy-build activation service; only Microsoft Support can investigate an account or activation-service failure.

If an official installer cannot be obtained or activated, retain the existing installation and use Office on the web or a supported Mac instead.

If Office 2016 was purchased separately

If the account owns a one-time-purchase Office 2016 for Mac license, Microsoft still documents a legacy 15.41 suite installer:

Back up Outlook first. If Outlook uses POP/IMAP and stores mail locally, open Outlook and select File > Export.
Quit all Office applications.
In Finder > Applications, move the affected Office applications to Trash.
Download and run the Office 2016 for Mac 15.41 installer from Microsoft’s rollback article.
Open each application and verify that About shows a version beginning with 15.^3^

That installer does not create an Office 2016 entitlement. It must be activated with a qualifying Office 2016 license. Microsoft distinguishes one-time-purchase Office from Microsoft 365, and a perpetual-license key does not activate the Microsoft 365/Mac App Store edition.^4^

Security limitation

Office 2016 for Mac has been unsupported since October 13, 2020, so it receives no security fixes, bug fixes, or technical support.^5^ High Sierra is also an obsolete platform, so a legacy installation should be treated as a temporary solution rather than a secure long-term configuration.

References