My computer failed to update Windows 11 version 25H2 Error 0xc1900101

Tina Konecny 25 Reputation points
2026-06-19T00:18:04.9266667+00:00

Now it won't shut down properly. It keeps trying to download and install but it doesn't work.
How do I go back to the last know working version of windows? Where has that option gone?

This is exactly why I don't like all of the updates all of the time. I like to stay on a working version. But lately I've let it update when it wants too, now I'm regretting that.

Windows for home | Windows 11 | Install and upgrade
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Answer accepted by question author
Ramesh Srinivasan 88,100 Reputation points Independent Advisor
2026-06-21T18:31:08.59+00:00

The fixlist.txt script ran fine. Please enable Memory Integrity now.

Once done, re-run the 25H2 upgrade.

Let me know how it goes.

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  1. AI answer

    2026-06-19T00:18:32.61+00:00

    Error 0xC1900101 is usually caused by a driver problem during a Windows upgrade, and failed upgrades can leave the system in an unstable state (for example, shutdown not working and Windows repeatedly trying to install the same update).

    To get back to a stable, working state and stop the repeated 25H2 attempts, use these steps in order:

    1. Run the Windows Update troubleshooter This can automatically fix some stuck or failed updates.
      1. Select Start > Settings > System.
      2. Select Troubleshoot > Other troubleshooters.
      3. Find Windows Update and select Run.
      4. Follow the on‑screen instructions and let it complete.
      After it finishes, restart the PC and see if shutdown works normally and if Windows Update stops looping.
    2. Repair system files and components This helps if the failed 25H2 attempt damaged system files.
      1. In the search box on the taskbar, type command prompt.
      2. Select Run as administrator.
      3. In the Command Prompt window, run these commands one at a time (press Enter after each): 
              DISM.exe /Online /Cleanup-image /Restorehealth
      sfc /scannow
      4. Wait for both commands to complete, then restart the PC.
      After the restart, try shutting down again and check if Windows Update still tries (and fails) to install 25H2.
    3. Use “Fix problems using Windows Update” to reinstall the current version Since the upgrade to 25H2 failed with 0xC1900101 and the system is unstable, reinstalling the current version of Windows (the last successfully installed version) is the supported way to get back to a clean, working build without losing files. This tool reinstalls the current version of Windows on the device and keeps apps, documents, and settings.
      1. Open Settings > System > Recovery (or use the shortcut ms-settings:recovery if available).
      2. Under Fix problems using Windows Update, select Reinstall now.
      3. In the Fix problems using Windows Update window, choose whether to allow the PC to automatically restart 15 minutes after installation completes.
      4. Select OK to start.
      5. The process takes you to Settings > Windows Update and downloads a repair version of the last operating system update that was successfully installed.
      6. When the reinstall completes, restart the PC (if it didn’t restart automatically).
      After this, the device will be back on the last known working version of Windows (the last successful build), and the failed 25H2 attempt should no longer be partially applied.
    4. Temporarily pause future updates (optional) Once the system is stable again and on a working version, updates can be paused for a while if desired.
      1. Go to Settings > Windows Update.
      2. Use Pause updates to temporarily stop automatic installs.
      This allows staying on the working version while deciding when to attempt 25H2 again.

    If 25H2 continues to fail with 0xC1900101 even after the repair, the next step (from Microsoft guidance) is to focus on drivers: ensure there is enough free disk space, run Windows Update multiple times, update or remove problematic third‑party drivers, and unplug non‑essential hardware before trying the upgrade again.

    References:

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  2. Ramesh Srinivasan 88,100 Reputation points Independent Advisor
    2026-06-19T01:04:56.4433333+00:00

    Hi,

    0xC1900101 is usually a driver-related issue. We need to remove some outdated drivers to ensure the 25H2 upgrade succeeds.

    How do I go back to the last know working version of windows? Where has that option gone?

    If you've upgraded from an earlier OS version, the option to go back to the previous version of Windows is valid for 10 days from the date of the upgrade.

    I like to stay on a working version.

    Please run winver.exe and post a screenshot of that dialog. The dialog shows your OS version and the build number.

    Note: Windows 11 version 24H2 will reach its end of support on October 13, 2026 for Home and Pro editions. After this date, these devices will no longer receive monthly security updates, bug fixes, or technical support.

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  3. Tina Konecny 25 Reputation points
    2026-06-21T16:46:46.6433333+00:00

    None of these things worked.

    What do I do now?

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