Why the Kernel Version Is Lower Than the OS Version After a Windows 11 Feature Update

Issue

After a Windows device installs a feature update such as KB5054156: Feature update to Windows 11, version 25H2 by using an enablement package, the device reports two build numbers that do not match:

• Operating system version: Microsoft Windows 11 Pro (10.0.26200)
• Kernel version: 10.0.26100.6584

You want to know why the kernel version still shows the older 26100 build (Windows 11, version 24H2) while the operating system reports 26200 (Windows 11, version 25H2), and whether the device is correctly updated.

Environment

• Automox (current agent release)
• Windows 11 devices updated to version 25H2 by an enablement package; Device Details in the console

Overview

This is expected behavior, not an error in the update or in how the device is reported.

Windows 11, version 25H2 (build 26200) and version 24H2 (build 26100) are built from the same core operating system with an identical set of system files. The 25H2 features are delivered ahead of time inside the monthly 24H2 quality updates, but they stay dormant until an enablement package (KB5054156) switches them on. Because the enablement package only activates features that are already present, it installs quickly and usually needs a single restart — it does not lay down a new set of system files.

The kernel is one of those shared system files. Since version 25H2 did not replace it, the kernel keeps its 26100-series version (for example 10.0.26100.6584), even though the overall operating system now reports version 25H2 as 10.0.26200.

Resolution

Use these checks to confirm the device is fully and correctly updated:

1. Open Devices and select the target device.
2. On the Summary, confirm the OS version reports 10.0.26200. This shows that the version 25H2 features are enabled.
3. Treat the two build numbers as expected on a 25H2 device:
   • OS version 10.0.26200 — version 25H2 features are turned on.
   • Kernel version 10.0.26100.xxxx — the shared core build, which version 25H2 does not change.
4. Confirm the device is current by checking the revision (the digits after the build — the xxxx in 26100.xxxx / 26200.xxxx). Microsoft ships monthly updates for both build numbers in lockstep, so an up-to-date device shows the current revision on both. To read the full build including the revision, see the companion article on finding the full OS build number for a device.

If the OS version reports 10.0.26200 and the revision is current, the device is fully patched — the lower kernel build is by design and requires no action.

Notes

• The kernel version is not the operating system build. On Windows 11 devices updated by an enablement package, the kernel build and the displayed OS build differ; the kernel value can be misleading if read as the OS build. Use the OS version (and the revision from the device's inventory) to confirm the update.
• This is the same pattern Microsoft has used for previous releases delivered as enablement packages (for example, version 22H2 and 23H2 shared the 22621/22631 core). The newer feature version increments the displayed build while the shared core files keep the earlier build number.
• To confirm the full build number, including the revision, see: How to Find the Full OS Build Number for a Device.
• Microsoft reference: KB5054156 — Feature update to Windows 11, version 25H2 by using an enablement package (https://support.microsoft.com/en-us/topic/kb5054156-feature-update-to-windows-11-version-25h2-by-using-an-enablement-package-4d307e2d-3028-4323-bb46-552cff491643).