Microsoft has paused the rollout of the KB5002907 Microsoft 365 update after users report that it deactivated, or in some cases completely removed, perpetual Office 2016 and Office 2019 installations.

KB5002907, titled "Optional update for out-of-date Microsoft 365 Apps installations," was released to help users update Microsoft 365 Apps installations that are more than 90 days out of date.

"This optional update is available only for Windows PCs with Microsoft 365 Apps installations that are more than 90 days out of date and use Current Channel or Monthly Enterprise Channel," explains the KB5002907 release notes.

"Installing the update can help the apps resume updating and move to a current build for the device's assigned update channel."

Microsoft says KB5002907 is an optional update offered through Windows Update and does not install automatically.

Shortly after the update was released, BleepingComputer was told by Christian Van Hautte, who runs an MSP in Belgium, that several of his customers suddenly found their perpetual Office installations showing as an "Unlicensed Product."

Van Hautte told BleepingComputer that five unrelated customers contacted his company within approximately ten minutes on September 24, with dozens of PCs affected across the organizations.

"The affected installations are all Office 2016 and Office 2019 Home & Business (perpetual/one-time purchase licenses)," Van Hautte told BleepingComputer.

"The common factor is KB5002907, an update released around September 23 and described as targeting 'outdated Microsoft 365 Apps installations' — but it is clearly also landing on perpetual (non-subscription) Office installs and breaking their license state."

Van Hautte said re-entering the original Office product key restored activation on affected systems.

Furthermore, Van Hautte warned that even though the update is listed as optional, it installed automatically on his customers' devices.

However, he later discovered that KB5002907 appears to remove and reinstall, or migrate the existing Office installation as part of its update process.

Van Hautte says that on systems with Office components of different architectures, such as a 32-bit Office 2016 or 2019 installation alongside a 64-bit Microsoft Access Runtime, the reinstall can fail because Microsoft Office setup does not allow mixing 32-bit and 64-bit Office products.

In those cases, he says the existing Office suite is removed but is not successfully reinstalled, leaving the device without Office.

Microsoft has not confirmed that mixed-bitness installations cause this behavior.

Reports from other administrators and users began appearing online at approximately the same time.

One Reddit user reported that multiple Office 2019 installations suddenly became deactivated and said entering the product keys again restored activation on at least some devices.

The user later updated the post to say the problem was not limited to Office 2019 and that some systems required signing into a Microsoft account and selecting the license rather than just entering the key.

In another report, an administrator said several unrelated customers contacted them after Office had been completely uninstalled.

"My Office 2019 and dad's Office 2016 installs both got nuked overnight... both are 100% legit keys purchased long ago," another user replied.

Similar reports appeared in the Microsoft forums, where multiple people reported similar issues after installing the update.

Microsoft pauses Microsoft 365 KB5002907 update

After BleepingComputer contacted Microsoft about the reports, the company confirmed that it had paused the update while investigating the issue.

"We are aware of these reports and have paused the update while we investigate. Additional customer guidance will be communicated via appropriate channels," a Microsoft spokesperson told BleepingComputer.

Microsoft also updated the KB5002907 support bulletin to acknowledge the problems.

"Microsoft is investigating reports of unexpected results on some devices running Office 2016 or Office 2019 after this update is installed," the company now says.

"To prevent additional devices from being affected, we have paused the rollout of this update."

Microsoft confirms that affected Office installations can suffer from two different problems.

In some cases, Office may appear unlicensed, and Microsoft recommends that customers reactivate their purchased product.

In what Microsoft describes as "rare cases," Office may be removed entirely. Microsoft instructs those users to download and reinstall their purchased copy of Office 2016 or Office 2019.

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