Prermanent install of Office for macOS lost activation and online re-activation gives 0x0 error ... how to fix?

Question

Prermanent install of Office for macOS lost activation and online re-activation gives 0x0 error ... how to fix?

W. Lee 40

I have a MacBook Pro running macOS Monterey. and I installed a permanent version of Office 2019 in October 2024 using a new retail key for a stand-alone license. The software was added to my account and I received a confirmation email at that time from Microsoft confirming the key # used and that it was added to my account. I have screen captures and copies of the confirmation email from Microsoft to document the successful installation and addition to my account in 2024.

I kept Office up-to-date as updates became available. This Office install remained activated, and all the Office apps worked fine until now. However, I have not used this particular laptop in a couple of months, and when I booted it today I found that Office had lost its activation. This seems to be for no apparent reason; there have been ZERO changes made to this laptop; not to the OS, not to the installed apps, nor to any of its hardware so as to trigger Office needing to be reactivated.

Today, when I went online and signed into my Microsoft account to reactivate, it showed several Office licenses being available to me (all stand-alone retail and matching the year and configuration of the 2019 Office for Mac that needed to be reactivated). However, when I selected any of these licenses from my account to reactivate, it just returned a pop-up message box, "An unknown error has occurred. The error code is: 0x0".

Firstly, why would Office lose activation on a particular computer just because it had not been used and online for a couple of months? This should not happen. Again, this is not an Office 365 subscription, it is a permanent local installed version of Office.

Secondly, "error code 0x0" doesn't really tell me anything ... any ideas what is going on and how to fix? Thanks!

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2 answers

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Answer 1

Kai-L 19,060 Microsoft External Staff Moderator

Dear W. Lee,

Good day, and I appreciate the detailed description of your issue. I can only imagine how frustrating and worrying it must be to boot up a laptop you've kept perfectly maintained, only to find Office suddenly deactivated for no apparent reason, especially when you have every confirmation and screenshot proving your licence was valid. Please rest assured this is not something you did wrong, and your licences and account are safe.

The 0x0 error is a widely reported macOS activation issue tied to a Microsoft-side change, not anything you did or didn't do on the laptop. Microsoft 365 and Office for Mac use a built-in digital certificate to validate licensing, and that certificate expired on July 13, 2026. Any affected install stops validating its licence around that date and either drops into reduced functionality mode or throws activation errors such as Unknown Error 0x0 / License Not Found. So the two months of inactivity is coincidental; you simply booted the Mac after the certificate expired. Your licences and your account are fine.

Since you are on macOS Monterey (which meets the macOS 12 minimum), it is worth trying the standard fix:

Close all Office apps.

Open Microsoft AutoUpdate (Finder > Applications > Microsoft AutoUpdate).

Select Update All and let it finish.

Reopen an Office app to test.

Important note:

I do want to be upfront with you here, so you're not left chasing a fix that may not come. Because your installation is Office 2019 for Mac, please be aware this version is no longer supported and may not be able to update to a build that includes the renewed certificate. If AutoUpdate shows no available update, or the 0x0 error persists after updating, that is the likely reason rather than anything on your side. Microsoft covers this exact scenario in a dedicated "If you have Office 2019 for Mac" section in the reference below.

If the update doesn't resolve it, here's what can keep you working:

Use Microsoft 365 on the web.

Subscribe to Microsoft 365. This gives you the latest Office apps with ongoing updates and support, and your existing files and documents will continue to work as normal

For reference:

Certificate update for Microsoft 365 apps on managed macOS and iOS devices - Microsoft 365 Apps

Update Microsoft 365 or Office on your macOS or iOS device | Microsoft Support

Unknown Error 0x0 or License not found error in Microsoft 365 or Office running on macOS

I hope this information helps clarify the situation and provides you with workable solutions. Should you have any further questions or need additional assistance, please don't hesitate to reach out. I'm always happy to help. Have a wonderful day!

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Kai-L 19,060 Reputation points Microsoft External Staff Moderator

2026-07-24T22:29:43.14+00:00

Dear W. Lee,

It has been a while and I am writing to see how things are going with this issue. If there’s anything else I can assist you with or if you need further clarification, please don’t hesitate to let me know, I’m here to help. Looking forward to hearing from you. Wishing you a great day ahead!
W. Lee 40 Reputation points

2026-07-25T23:05:30.05+00:00

Hello, Sorry for the late reply, but I missed this 2nd discussion and am a little confused as to what happened to this post and thread; it appears that an early draft of my same question (the early draft on this page that you responded to) got posted along with the final version on another page. The question on that other page already had been answered, so sorry for the apparent duplication here.

In any event, it was confirmed from other sources that Microsoft had not only discontinued update support for Office 2019, but also let the certificate expire that was needed to communicate with the MS server. The unnerving thing about what resulted was that not only can't new installations be activated, but existing installations also lost their activation of Office 2019 for macOS ... this seems like an over-reach on Microsoft's part, and there is considerable frustration and anger being expressed in online discussions regarding how MS has handled this by disabling "permanent" stand-alone licenses without notice. Apparently, this certificate lapse issue did not affect the Windows PC version of Office 2019.

As for my situation, I simply uninstalled Office 2019 for macOS and replaced it with an Office 2021 installation and key that I had available.
Stefan Blom 351.5K Reputation points MVP Volunteer Moderator

2026-07-25T23:14:00.21+00:00

As for my situation, I simply uninstalled Office 2019 for macOS and replaced it with an Office 2021 installation and key that I had available.

I'm glad you got it sorted.

Side-note: I don't think any messages have been lost in the thread. You seem to be active in at least one more thread on the same topic as well: https://learn.microsoft.com/en-us/answers/questions/5955499/office-2019-for-macos-lost-activation-for-no-appar .
W. Lee 40 Reputation points

2026-07-25T23:34:16.38+00:00

Thanks for the heads-up regarding the "lost thread" ... I think I figured it out; actually, I had (2) separate topics for (2) different computers and Office versions and those were the only ones that I was aware of posting. However, unbeknownst to me, there was some webpage glitch while editing one of those posts so that an unintended draft copy became a 3rd post (this one) that I was not aware of until just now.
Stefan Blom 351.5K Reputation points MVP Volunteer Moderator

2026-07-25T23:36:38.0633333+00:00

However, unbeknownst to me, there was some webpage glitch while editing one of those posts so that an unintended draft copy became a 3rd post (this one) that I was not aware of until just now.

Unfortunately, web page glitches are rather common in the Q&A forums. :-(
Kai-L 19,060 Reputation points Microsoft External Staff Moderator

2026-07-27T21:22:16.4666667+00:00

Dear W. Lee,
Thank you for coming back to share the outcome. I'm glad to hear you were able to get back up and running by moving to Office 2021. If you have any further questions or need additional assistance down the road, feel free to post back. Not only I, but other professionals in the forum are always here to help. Thank you again for being a valued member of the Q&A community and I wish you all the best!

Answer 2

Stefan Blom 351.5K MVP Volunteer Moderator

Sorry to be the bearer of bad news, but Office 2019 won't work anymore. You now need an Office license that lets you install at a minimum Office release 16.83. See https://support.microsoft.com/en-us/support/known-issues/unknown-error-0x0-license-not-found-error-microsoft365-macos , https://www.brandwares.com/bestpractices/2023/03/most-recent-office-you-can-run-best-practices/ and https://learn.microsoft.com/en-us/microsoft-365-apps/mac/certificate-update-mac-ios .

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