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Windows 11 26H2 (KB5121794): How to Get the 2026 Update
Written by Windows 11 Field Guide Editorial Team · Updated
Windows 11 26H2 is the 2026 feature update for Windows 11. On most PCs that are already up to date it arrives as a tiny download called an enablement package, KB5121794, rather than a full reinstall. This guide explains what that package does, which PCs can take it, what has to be installed first and how to get it from Windows Update.
What KB5121794 actually does
Microsoft’s support article for KB5121794 says Windows 11 versions 24H2, 25H2 and 26H2 share a common core operating system. Because of that, the 26H2 features are already included in the latest monthly quality update for 24H2 and 25H2, but they are left in an inactive, dormant state.
The enablement package is what Microsoft calls a small, quick-to-install “master switch”. Installing it activates the 26H2 features and changes the version number, with a single restart. Nothing large is downloaded at that point, because the code is already on the PC.
Microsoft used the same approach a year earlier, when KB5054156 moved PCs from 24H2 to 25H2. For the background on how this shared branch works, see our explainer on the Windows 11 enablement package. This page sticks to the practical side of 26H2 itself.
Which PCs can get it
According to Microsoft’s article, KB5121794 applies to:
- Windows 11 version 24H2
- Windows 11 version 25H2
in the Home, Pro, Enterprise, Education, Enterprise multi-session and IoT Enterprise editions.
If winver shows 23H2, 22H2 or older, the enablement package is not for you. Those versions are on an older core, so moving to 26H2 means a full feature update from Windows Update, or an in-place upgrade with the Installation Assistant or an ISO.
The update you need first
The package will only install on a PC that already has a recent cumulative update. Microsoft lists the prerequisite as the 22 September 2026 preview update, KB5124010, or any later cumulative update. In practice, if you have installed the October 2026 monthly security update or anything newer, you meet it.
How to install Windows 11 26H2
- Press Windows key + R, type
winverand press Enter to confirm you are on 24H2 or 25H2. - Open Settings > Windows Update and select Check for updates. Install the latest cumulative update and restart if asked.
- Go back to Settings > Windows Update. If Windows 11, version 26H2 is available is listed, select Download & install. To read about it first, select See what’s in this update.
- Restart when prompted.
- Run
winveragain. It should now show version 26H2.
Microsoft also lists the Microsoft Update Catalog and WSUS as ways to get the package. Those are mainly for IT administrators managing many PCs.
If 26H2 is not offered
Work through these in order:
- Prerequisite missing. Install every pending cumulative update, restart and check again.
- Older version. A PC on 23H2 or earlier will not see the enablement package. See Windows 11 feature update for the full route.
- Updates paused. If you paused updates, resume them.
- Work or school PC. If the device is managed by an organisation, its IT team decides when feature updates are allowed.
- Gradual rollout. Microsoft offers feature updates to devices in stages. If everything else checks out, wait and check again later.
- Installation fails. See Windows 11 update failed and Windows 11 update stuck for error-by-error fixes.
Should you install it now?
Each Windows 11 version has a fixed support period, and a new version starts a fresh one. Microsoft’s release information shows 24H2 Home and Pro have already reached end of updates, so a PC still on 24H2 Home or Pro should move to 25H2 or 26H2 to keep receiving security fixes. On 25H2 there is less urgency, but since the switch is quick and keeps your files and apps, there is little reason to put it off for long. If you rely on specialist software or older hardware drivers, check with the vendor first.
Can you go back?
After a feature update, Windows usually keeps a short window in which you can return to the previous version from Settings > System > Recovery. Our guide to uninstalling a Windows 11 update covers this and the limits on how long the option stays available.
Frequently asked questions
What is KB5121794?
It is the enablement package that moves a Windows 11 PC from version 24H2 or 25H2 to version 26H2. Microsoft describes it as a small, quick-to-install switch that activates features already delivered in monthly updates.
Which PCs can install KB5121794?
Microsoft's support article lists Windows 11 versions 24H2 and 25H2, in the Home, Pro, Enterprise, Education, Enterprise multi-session and IoT Enterprise editions.
Do I need another update before 26H2?
Yes. Microsoft lists the 22 September 2026 preview update, KB5124010, or any later cumulative update, as the prerequisite. Installing the latest monthly update covers this.
How long does the 26H2 update take?
From 24H2 or 25H2 it needs a single restart, because the new code is already on the PC. It is much quicker than an older-style feature update.
Why don't I see 26H2 in Windows Update?
Usually because the prerequisite update is missing, the PC is on an older version such as 23H2, the PC is managed by an organisation that controls updates, or the rollout has not reached your device yet.
Will 26H2 delete my files or apps?
No. A feature update keeps your files, apps and settings. A backup before any big update is still a good habit.
Sources
Windows 11 Field Guide Editorial Team
Editorial team
The Windows 11 Field Guide team writes and updates independent Windows 11 guides and checks each step against Microsoft's documentation and the current Settings app.
