Windows 11 Won't Update? 10 Fixes That Work (2026)

A Windows 11 update that refuses to install is one of the most common PC headaches, and it’s almost always fixable without a reinstall. The cause is usually a stuck update cache, low disk space, or a corrupted system file. We tested the official fixes on a PC that kept failing an update and ranked them so the quick, safe steps come first and the heavier repairs come last.

#Why Won’t Windows 11 Update?

Update failures look mysterious, but they cluster into a few causes. The most common are a stuck or corrupted update cache, not enough free disk space, damaged system files, or a temporary glitch a restart would clear.

The good news is that you don’t have to guess which cause applies. Working through the fixes in order naturally rules each one out, starting with the easiest.

If your update isn’t failing but instead frozen at a percentage, that’s a slightly different problem covered in our guide on a Windows 11 update stuck mid-install. For an update that errors out or won’t start, the steps below apply.

#First Steps: Troubleshooter, Space, and Restart

Always begin with the three fastest fixes, because they resolve most cases in minutes. Start with the built-in troubleshooter.

Open Settings, System, Troubleshoot, then Other troubleshooters, and run the one labeled Windows Update. According to Microsoft’s update troubleshooting guide, this tool “will automatically run diagnostics and attempt to fix most of the problems,” then prompts you to restart.

Next, check your free space. Microsoft states that a 64-bit Windows upgrade needs at least 20 GB free, so clear room if you’re tight. Then do a full restart, which alone clears the temporary glitches behind plenty of failed updates. If a specific code appears, like error 0x800705b4, match the fix to that code.

#Resetting Windows Update Components

If the basics don’t work, the update cache itself is probably corrupted. Resetting it forces Windows to download fresh update files from scratch.

You do this in an elevated Command Prompt by stopping the update services, renaming the SoftwareDistribution and catroot2 folders so Windows rebuilds them, then restarting the services. Renaming rather than deleting keeps a backup just in case.

This single step clears a large share of stubborn update failures, since the corrupted cache is a frequent culprit. A simpler version is to manually delete old Windows update files, which clears the same cache through a friendlier interface if the command line feels intimidating.

#Repairing System Files With SFC and DISM

When the cache reset doesn’t stick, corrupted Windows system files are the next suspect. Two built-in commands fix them, and the order matters.

Run DISM first, then SFC. Microsoft confirms that you “should run DISM prior to running the System File Checker,” because DISM repairs the underlying Windows image that SFC then uses as a clean source. In an admin Command Prompt, run DISM.exe /Online /Cleanup-image /Restorehealth, wait for it to finish, then run sfc /scannow.

Let each command run fully before closing the window. The DISM scan can take several minutes, and SFC then replaces any damaged protected files with good copies. Together they repair the deep file corruption that a cache reset alone can’t touch.

#When to Update Manually or Use the Installation Assistant

If Windows Update is too broken to fix itself, you can sidestep it entirely. Microsoft offers manual tools that install the latest version directly.

Download the Windows 11 Installation Assistant from Microsoft’s official site, run it, and it upgrades your PC to the current build without relying on the Windows Update pipeline. It’s the most reliable way to force an update through when the normal route keeps failing.

Before you do, confirm your hardware is eligible, since an ineligible PC fails updates for a different reason. Our guide on checking whether your PC can run Windows 11 covers the requirements. If even the Installation Assistant struggles, booting into Safe Mode first can clear interfering software.

#Should You Disable Antivirus or a VPN to Update?

Sometimes the thing blocking your update isn’t Windows at all. A third-party antivirus or an active VPN can quietly interfere with the download.

Microsoft’s Windows Update errors guide recommends disabling a VPN and pausing non-Microsoft antivirus while you update. In our testing, an update that failed twice in a row succeeded immediately after we turned off an active VPN and let it retry. Re-enable both protections the moment the update finishes.

Try this before the heavier repairs if you run either tool. It costs nothing and takes seconds.

#Bottom Line

When Windows 11 won’t update, resist the urge to reinstall. Work the list in order: run the Windows Update troubleshooter, free up disk space to at least 20 GB, and restart. If that fails, reset the Update components by renaming the SoftwareDistribution folder, then repair system files by running DISM and then SFC.

Those steps fix the overwhelming majority of update failures for free. Only if the whole Windows Update system stays broken should you reach for the Installation Assistant, which installs the latest build directly and almost always succeeds.

#Frequently Asked Questions