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Windows 11, version 25H2 Failed to install - error 0x800f0991. How do I fix the problem?

Mark Willman 0 Reputation points
2025-11-05T01:32:43.0866667+00:00

I have tried to install Windows 11, version 25H2 several times. It downloads but fails to install. I get the following error: 0x800f0991. I have tried running the Windows Troubleshooter with no success. What can I do to install this update?

Windows for business | Windows Client for IT Pros | Devices and deployment | Set up, install, or upgrade
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  1. Quinnie Quoc 7,400 Reputation points Independent Advisor
    2025-11-05T02:16:24.9966667+00:00

    Hello,

    Thank you for your question. The error code 0x800f0991 typically indicates a problem with component store corruption or missing system files that prevent the update from completing successfully. Since the Windows Troubleshooter didn’t resolve the issue, I recommend the following steps:

    1. Run the following commands in an elevated Command Prompt (Run as Administrator):

    Code

    DISM /Online /Cleanup-Image /RestoreHealth  
sfc /scannow

     2.  After both scans complete, restart your PC and try the update again via **Settings > Windows Update**.

    If the issue persists, you can perform an in-place upgrade using the Windows 11 Installation Assistant, which preserves your files and apps while refreshing system components.

    If this helps resolve the issue, feel free to mark this answer as accepted so others can benefit too.

    Thank you so much!!!!

    Best regards,

    QQ

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