If you opened Word, Excel, or Outlook recently and saw a banner that says "Unlicensed Product" — or worse, found that Microsoft Office has completely disappeared from your computer — you're not imagining things, and you didn't do anything wrong. A recent Microsoft update is the cause.
Here's what happened, who's affected, and what to do about it.
What Happened?
On September 23, 2026, Microsoft released an update called KB5002907, titled "Optional update for out-of-date Microsoft 365 Apps installations." It was designed to force-update Microsoft 365 (subscription) installations that had fallen more than 90 days behind on updates.
The problem: it's also hitting computers running Office 2016 and Office 2019 — the one-time purchase versions that have nothing to do with Microsoft 365. These are fully paid, fully legitimate licenses. And after the update installs, Office either shows as "Unlicensed Product" or, in some cases, gets completely removed from the machine.
Microsoft has acknowledged the issue and paused the rollout while they investigate.
Who's Affected?
Update: KB5002907
Affected products: Office 2016 and Office 2019 (perpetual license / one-time purchase editions)
What it does: Deactivates the license (shows "Unlicensed Product" across Word, Excel, Outlook, etc.) or, in rarer cases, completely removes the Office installation.
How it got there: Although Microsoft says KB5002907 is "optional" and shouldn't install automatically, multiple businesses have reported it installed on its own through Windows Update without anyone clicking anything.
How to Tell If This Affected You
- Open any Office application (Word, Excel, Outlook)
- Look for a yellow or red banner at the top that says "Unlicensed Product" or "Product Activation Required"
- If Office apps are missing entirely from your Start menu, the update may have removed them
- Check Windows Update history: go to Settings → Windows Update → Update history and look for KB5002907
How to Fix It
Microsoft has confirmed two scenarios and the fix for each:
Scenario 1: Office Says "Unlicensed Product"
Your Office installation is still there — the update just knocked out the license activation. You need to re-enter your original product key.
To do this:
- Open any Office app (Word, Excel, etc.)
- Click the activation prompt or go to File → Account
- Click "Change Product Key" or "Activate Product"
- Enter your original Office 2016 or Office 2019 product key
If you purchased Office through a Microsoft account, you may need to sign in at account.microsoft.com/services and select your license instead of entering a key.
Don't have your product key? Check your email for the original purchase receipt, look for a card or sticker that came with your computer, or check with whoever set up your Office installation. If your business bought volume licenses, your IT admin will have the key.
Scenario 2: Office Was Completely Removed
In what Microsoft describes as "rare cases," the update removes Office entirely. This appears to happen more often on systems that have mixed-architecture Office components — for example, a 32-bit Office 2016 installation alongside a 64-bit Microsoft Access Runtime.
The update appears to attempt a reinstall as part of its process. When it encounters mismatched architectures, the reinstall fails silently, and Office just disappears.
If this happened to you:
- Go to account.microsoft.com/services and sign in with the Microsoft account tied to your Office purchase
- Find your Office 2016 or Office 2019 license and click Install
- If you used a product key without a Microsoft account, download the installer from setup.office.com and enter your product key
- For volume license installations, contact your IT administrator for the deployment package
What About November Patch Tuesday?
November's Patch Tuesday is next week — November 10, 2026. Microsoft has paused the KB5002907 rollout, so it shouldn't reinstall if you've already dealt with it. But this is a good reminder to check your Office installations across all your machines before the next round of updates lands. Catching a deactivated license on one PC is annoying. Discovering it across an entire office on a Monday morning is a different story.
While we're on the subject of updates: if your machines are still running Windows 11 version 24H2 Home or Pro, those editions reached end of support on October 13. That means no more security patches. Microsoft is also warning that devices on unsupported Windows versions will lose access to Windows Update entirely after certificate rotations in May and June 2027. If you've been putting off upgrades, that clock is ticking.
October Update Issues — Quick Status Check
Since our last post about the October Windows 11 update problems, here's where things stand:
- Remote Desktop broken for non-admin users — Resolved. Microsoft shipped the fix in KB5127936 on October 28. If you install that update, the RDP issue is gone.
- USB audio devices (Code 10 / no sound) — Still broken. No permanent fix yet. Microsoft still lists this as "Mitigated" only.
- Domain trust, Dolby audio crashes, black screens — All resolved in previous updates.
The Bottom Line
If your Office suddenly says "Unlicensed" — re-enter your product key. If it disappeared entirely — reinstall it from your Microsoft account or setup.office.com. The update causing this (KB5002907) has been paused, but the damage may already be done on some machines.
This is the kind of thing that affects one PC and you shrug it off — or it hits 20 machines across a business and your morning goes sideways. Worth checking proactively.
Sources: Microsoft KB5002907 Support Bulletin · Windows Release Health Dashboard · BleepingComputer