Microsoft says unexpected Windows Server 2025 automatic upgrades were due to faulty third-party tools

• Some firms had their Windows Server unexpectedly upgraded to new 2025 version
• Microsoft blames third-party tools after widespread issues reported
• Some are claiming there was a bug on Microsoft’s side

Microsoft’s recent launch of Windows Server 2025 appears to still be causing aftershocks after many companies said they were automatically upgraded to the new software.

Multiple Windows Server 2019 and 2022 systems were reportedly unexpectedly upgraded to Windows Server 2025 overnight, and Microsoft and third-party patch management service providers are now shifting blame amongst themselves.

The bug now finally appears to be fixed, but Microsoft is yet to explain to its customers how the upgrade can be rolled back.

Procedural error

“Some devices upgraded automatically to Windows Server 2025 (KB5044284). This was observed in environments that use third-party products to manage the update of clients and servers,” Microsoft explained. “Please verify whether third-party update software in your environment is configured not to deploy feature updates. This scenario has been mitigated.”

In other words, it’s not Microsoft – it’s you. The company also added the update had the “DeploymentAction=OptionalInstallation” tag, which patch management tools should read as being an optional, rather than recommended update.

Upgrading to a brand new operating system comes with many questions and risks, and in this case, some companies didn’t even have the necessary license.

Microsoft didn’t name any names, but BleepingComputer found many of Heimdal’s clients were affected by the issue. The company blamed the bug on a “procedural error on Microsoft’s side, both with the speed of release…