Windows Update Failure

Since sfc /scannow and DISM /Online /Cleanup-Image /RestoreHealth already completed successfully, the next supported steps are:

1. Run the Windows Update troubleshooter
   Go to Start > Settings > System > Troubleshoot > Other troubleshooters.
   Find Windows Update and select Run. Follow the on-screen steps.
2. Clear the Windows Update cache
   This removes potentially corrupted update files.
   • Press Win + R, type services.msc, and press Enter.
   • Locate Windows Update, right-click it, and select Stop.
   • Go to C:\Windows\SoftwareDistribution.
   • Delete all files and folders inside that folder.
   • Return to Services, right-click Windows Update, and select Start.
3. Reset the SoftwareDistribution and Catroot2 folders from an elevated Command Prompt
   Microsoft marks this as an advanced step and it requires administrator permissions.
   • Search for command prompt, select Run as administrator, then run these commands one at a time:
     • net stop bits
     • net stop wuauserv
     • ren %systemroot%\softwaredistribution softwaredistribution.bak
     • ren %systemroot%\system32\catroot2 catroot2.bak
     • net start bits
     • net start wuauserv
   • Restart the PC after the commands complete.
4. Temporarily remove third-party antivirus or security software
   Third-party security software can block Windows 11 updates. Before uninstalling, make sure the reinstall method and any required product keys are available. After removal, try Windows Update again.
5. Disconnect nonessential external hardware
   Remove USB drives, docks, printers, scanners, and other nonessential devices, then retry the update.
6. Check free disk space
   Windows 11 upgrades require at least 16 GB free space for a 32-bit OS or 20 GB for a 64-bit OS.
7. Try a clean restart
   A clean restart starts Windows with a minimal set of drivers and startup programs, which can help if another service or app is interfering with the update.
8. If update failures continue, use the built-in repair reinstall path
   A Microsoft Q&A accepted answer recommends trying the repair installation through Settings instead of using the ISO method.

If the failure is still limited to this update after these steps, the most relevant supported path is to reset the update components, remove third-party security software, and retry with minimal startup items loaded.

References:

• [Windows 11](https://support.microsoft.com/windows/deployment/updates-lifecycle/troubleshoot-problems-updating-windows#general-troubleshooting)
• [Windows 11](https://support.microsoft.com/windows/deployment/updates-lifecycle/troubleshoot-problems-updating-windows#most-common-windows-update-problems)
• Windows 11 Home Single Language update keeps failing — had to complete update using ISO file. How to fix permanently? - Microsoft Q&A
• How to fix error 0x800f081f for 2026-06 Security Update (KB5094126) (26200.8655) for Windows 11 ver 25H2 for ARM64 processor - Microsoft Q&A