KB5120998 for Windows 11 direct download for early access to September 2026 features

Windows 11 KB5120998 (Build 26200.9278) is now available as an optional install for versions 25H2 and 24H2.
You can install the update through Windows Update or download the standalone “.msu” package from the Microsoft Update Catalog.

The Windows 11 update KB5120998 (builds 26200.9278 and 26100.9278) is now available for versions 25H2 and 24H2. This is an optional, non-security update that Microsoft is making available through Windows Update, and you can also download the standalone .msu package from the Microsoft Update Catalog.

For Windows 11 25H2, KB5120998 advances the system to build 26200.9278, while version 24H2 moves to build 26100.9278. The update includes production-quality improvements across several areas of the operating system and previews changes Microsoft is expected to include in the September 2026 Security Update.

This isn’t simply another routine cumulative update. The company is using this release to introduce several noticeable changes to Windows 11, including new Taskbar customization options, Start menu improvements, Windows Search refinements, and updates to File Explorer, Windows Share, Task Manager, networking, and other parts of the operating system.

Because KB5120998 is an optional preview update, you don’t have to install it immediately. If you want to try the latest improvements early, you can install it from Settings > Windows Update when the update appears. You can also download the appropriate standalone package manually from the Microsoft Update Catalog.

Microsoft is also expected to include these changes in the next security update, but some features may roll out gradually and may not become available immediately after installing the update.

Windows 11 KB5120998 direct download

You can use this link to download the update manually for versions 25H2 and 24H2 (x64 and ARM64) from the Microsoft Update Catalog website.

Windows 11 KB5120998 download / Image: Mauro Huculak

If Windows Update isn’t working correctly or you need to update multiple computers, downloading the “.msu” package may be easier.

Once you download the package to your device, double-click it to apply the update.

One thing to note is that the update KB5120998 is also available for version 26H2 as a pre-release.

Install the September 2026 non-Security Update

To install the update through Windows Update manually, follow these steps:

Open Settings on Windows 11.
Click on Windows Update.
Check the “Get the latest updates as soon as they’re available” toggle switch to download updates before they roll out automatically to everyone.
Click the Check for updates button.
Click the “Download and install” option to apply a preview of an upcoming update of Windows 11.
Click the Restart now button.

After you complete the steps, the update will install on your computer.

What’s new in the September 2026 Update

Windows 11 builds 26200.9278 and 26100.9278 (KB5120998) are available now in the Stable channel with major customization upgrades, including a movable and resizable Taskbar and new Start menu size options.

Windows Search gets interface refinements and more control over web and Microsoft Store suggestions.

Microsoft begins rolling out Administrator Protection, while File Explorer, Windows Share, Task Manager, networking, and other parts get smaller improvements.

As with other preview releases, some features may roll out gradually and might not be available immediately after installing the update.

Should you install this update?

Because this is an optional preview update, you don’t need to install it right away. If you’re experiencing one of the issues addressed in this release or want early access to the upcoming improvements, installing the update may be worthwhile.

Otherwise, you can wait until September 11, 2026, when Microsoft will automatically deliver these fixes and enhancements as part of the regular monthly security update.

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