KB5002907 paused: an optional update deleted Office 2016

An optional Windows Update took Office off machines this week. Microsoft has paused the rollout of KB5002907 after reports that it left perpetual Office 2016 and Office 2019 installs unlicensed — or, on some devices, removed them entirely. If your shop still runs a boxed copy of Office on a couple of front-desk PCs, this one landed on you.

What actually happened

Per Microsoft's own KB page and BleepingComputer:

• The update's job was repair, not features. KB5002907 targets Microsoft 365 Apps installs that are more than 90 days out of date on Current Channel or Monthly Enterprise Channel, and uses Windows Update to bring them current. It covers Windows 11 23H2 through 26H1, Windows 10 22H2, and Windows Server 2019/2022/2025.
• The repair action is what broke things. Microsoft writes that "some devices were left without functioning versions of Microsoft 365 Apps or Office." Two failure modes: Office reports itself as an unlicensed product, or Office is gone from the machine.
• The victims are perpetual licenses. The reports center on Office 2016 and Office 2019 Home & Business — one-time purchases, not subscriptions. Mixed-architecture installs (32-bit Office next to a 64-bit Access Runtime) reportedly failed hardest on reinstall.
• Microsoft paused it. The stated resolution is to reactivate the purchased product if it shows unlicensed, and reinstall the purchased product if it was removed. There is no patch for the patch yet.
• Optional did not mean opt-in. Microsoft describes KB5002907 as optional and not automatic. Users reported it arriving on its own anyway.

Why an optional update matters for your business

Nobody budgets a day for reinstalling Office. The cost here is not the license — you already own it. The cost is the product key you cannot find, because it was on a card in a box in 2017, or in an email to an employee who left in 2021.

That is the actual lesson, and it has nothing to do with Microsoft. Perpetual software is an asset with no recovery path unless you built one. Subscriptions reinstall from an identity; boxed licenses reinstall from a string of characters somebody has to have kept. If your key inventory is "Dave probably knows," you do not own that software in any operational sense.

Two things to do this week. First, find your keys and put them somewhere the business controls — a password manager vault, not a spreadsheet on one desktop. Second, check whether Windows Update is allowed to hand your fleet optional updates unattended. On a workstation that runs a boxed Office, or any old line-of-business app, deferral is not laziness. It is the only test window you have.

Sources: Microsoft Support: KB5002907, BleepingComputer.