Microsoft pauses KB5002907 update after reports it deactivates perpetual Office licenses

The KB5002907 update was released on September 23 as an optional update through Windows Update for Microsoft 365 Apps installations more than 90 days out of date. However, shortly after release, reports emerged that the update was also affecting perpetual Office licenses.

Christian Van Hautte, who runs an MSP in Belgium, told BleepingComputer that five unrelated customers contacted his company within ten minutes on September 24, with dozens of PCs affected. 'The affected installations are all Office 2016 and Office 2019 Home & Business perpetual licenses,' he said. 'The common factor is KB5002907, an update released around September 23 and described as targeting outdated Microsoft 365 Apps installations — but it is clearly also landing on perpetual Office installs and breaking their license state.'

Van Hautte said re-entering the original product key restored activation. He also noted that even though the update is listed as optional, it installed automatically on his customers' devices. Furthermore, he found that the update appears to remove and reinstall the existing Office installation, which can fail if the system has mixed 32-bit and 64-bit Office components, leaving the device without Office.

Microsoft has paused the update but has not confirmed the root cause or whether mixed-bitness is a factor. Reddit users reported similar issues, with some able to reactivate by re-entering product keys.

The update was designed for Microsoft 365 Apps installations on the Current or Monthly Enterprise channels that are severely out of date. It is not intended for perpetual license versions, making the impact unexpected.

Why This Matters

Users with perpetual Office licenses may lose access to their software unexpectedly; IT administrators may face significant downtime and support requests.
The incident highlights the potential for Microsoft's update mechanisms to affect software beyond their intended scope, raising questions about quality assurance.
Affected users can restore activation by re-entering product keys, but in mixed-architecture cases, Office may be entirely removed.

Background

KB5002907 is an optional update released September 23, 2026, intended to bring severely outdated Microsoft 365 Apps installations up to date. It is offered through Windows Update only for devices on the Current or Monthly Enterprise channels with Microsoft 365 Apps more than 90 days out of date. However, users with perpetual Office 2016 and 2019 licenses reported the update deploying on their systems, deactivating or removing their Office installations.

Key Perspectives

[Microsoft]: The company has paused the update but has not issued a statement confirming the root cause or clarifying how it affected non-365 installations. [Affected Users and MSPs]: Christian Van Hautte, an MSP owner, reported that the update installed automatically despite being optional, deactivating perpetual licenses across multiple clients. He also warned that mixed 32-bit and 64-bit Office components could cause complete removal. [Critics]: The incident raises concerns about how Microsoft labels updates as optional and whether the distribution mechanism adequately excludes unintended software.

What to Watch

Microsoft's official response: a permanent fix or updated update that exempts perpetual licenses.
Whether Microsoft will provide guidance for users who lost Office entirely due to mixed-architecture issues.
Broader implications for the update system: potential changes to how optional updates are flagged and distributed.

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