Problem with installing Windows 11 25H2 Pro Insider Preview Feature Update (26220.9022)

Question

So everytime I download and install the Insider Preview Feature Update (26220.9022) it asks to restart device as usual. However, when restarting device, it will show update completed 100% and then the screen will flicker and turn off while my CPU, Keyboard and Mouse is all active. There is nothing on screen. Its not even a black screen, just turned off with no activity. If I try to press the control buttons on my monitor, it shows the monitor control menu for a split second before turning off again. I have tried every possible troubleshooting known to me or found online with no success. Then I try to hard reset/restart the PC, and it will turn on. But then when I check the Windows Update status under settings, it shows Failed to install "error code 0xc1900101". This has happened multiple times now and I have no clue what to do and apparently I have time only till 11th Aug, '26 till my current build expires. Someone please help!

Answer 1

Hi Alex008,

I know how frustrating it is when the new Insider build update keeps rolling back after reaching 100%, especially when the certificate is close to expire date. The AI answer has already covered the common troubleshooting steps for this situation, have you tried them out? If the situation hasn't improved, I think it's better to gather more information first:

• Check whether the failure generated Windows Setup logs, e.g.
  • C:\$WINDOWS.~BT\Sources\Panther\setupact.log
  • C:\$WINDOWS.~BT\Sources\Panther\setuperr.log
  • C:\$WINDOWS.~BT\Sources\Rollback\setupact.log
  • C:\Windows\Logs\MoSetup\BlueBox.log
• Download and run SetupDiag from Microsoft:
  • Search 0xC1900101 and note down other information linked to it.
  • The extended code may identify the phase and operation that failed.
• Visit the PC or motherboard manufacturer and install the latest:
  • BIOS/UEFI firmware package
  • Chipset, storage controller, GPU drivers.

Surprising number of Insider update failures are also linked to storage controller drivers. Even if you have removed all additional devices, their drivers can leave some leftovers, which are common contributors to 0xC1900101 rollback cases. Open Device Manager and uninstall any entries you don't recognize or not used anymore.

In addition, there's actually been reports from community members facing issues with updating the latest Insider builds. For example, Error 0x80070005 when updating Windows Insider to 29639.1000 for 7 consecutive times..., or My computer cannot update to the new preview experience system, and so on.

Disclaimer: The latter thread is in another language. It's referenced here only because it might be related to your issue. You may use a translation tool, but please be mindful that some meanings may be translated inaccurately.

Although the error codes in the issues above are not identical to what you're experiencing, the fact that multiple users are encountering upgrade failures / rollbacks with Insider builds makes it possible that this might not be solely a problem with your device. So besides trying to fix this yourself, consider:

1. Report this to Microsoft engineering team via Feedback Hub (press Win + F)
2. Describe the issue, and share the logs acquired above (if possible), especially:
   1. setupact.log and setuperr.log
   2. Output from SetupDiag.

If you wish, you can share them with me too and I can help reviewing to see if we can find the specific components that caused the failure. To protect your personal information, please upload those files to OneDrive and share the link via Private Message.

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Answer 2

For error 0xC1900101 during a Windows 11 Insider/feature update, the most relevant supported steps are driver and boot-environment troubleshooting.

1. Check Device Manager for driver problems
   • Open Device Manager.
   • Look for any device with a yellow exclamation mark.
   • For any flagged device, right-click it and choose Update driver.
   • If that does not help, try Uninstall for the problem device, then restart.
   • This matters because 0xC1900101 is associated with driver-related upgrade failures.
2. Disconnect newly added or unnecessary hardware
   • Shut down the PC.
   • Remove any recently added hardware and disconnect nonessential external devices.
   • Try the update again.
   • Unexpected restarts and stop code issues can be caused by hardware devices or their drivers.
3. Start in Safe Mode if normal startup is unstable
   • If the system is difficult to recover after the failed update, start in Safe Mode first.
   • From Safe Mode, continue with the remaining checks.
4. Install all currently available Windows updates first
   • Go to Start > Settings > Windows Update > Check for updates.
   • Install everything offered, then restart and retry the Insider build.
5. Ensure enough free disk space
   • Keep at least 10% to 15% free space available on the system drive.
   • Low free space can interfere with update and recovery operations.
6. Temporarily remove third-party security software
   • For 0xC1900101 upgrade failures, remove third-party security software before retrying.
   • Have the installer or product key available before removal.
7. Run disk and system image repair tools
   • Open Command Prompt as administrator.
   • Run:

          chkdsk /f C:
     

     Restart if prompted.
   • Then run:

          DISM.exe /Online /Cleanup-image /Restorehealth
     

   • Both commands require administrator permissions.
8. Perform a clean boot before retrying the update
   • A clean boot can reduce interference from third-party services during setup.
   • This is specifically recommended for Windows upgrade/install errors.
9. If the issue started after repeated failed restarts, avoid registry workarounds
   • Do not manually delete or change registry keys to bypass restart/update state. This is explicitly warned against because it can cause later issues.
10. If the update still fails, use the supported recovery path

• Use System Restore or another option under Recovery options in Windows 11.
• This is the supported next step when the standard troubleshooting path does not resolve repeated stop code or restart failures.

The screen turning off after reaching 100% is consistent with a failure during the reboot/driver phase, which aligns with the documented 0xC1900101 guidance to focus on drivers, third-party security software, disk repair, DISM, and clean boot.

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References:

• Get help with Windows upgrade and installation errors
• Troubleshooting Windows unexpected restarts and stop code errors
• The computer needs to restart before Setup can continue in Exchange Server