Windows 11 Installation Failed(Windows Insider Preview ISO)

Question

Windows 11 Installation Failed(Windows Insider Preview ISO)

Jeremy Green 0

I received an error when attempting to launch a game that was due to a .dll problem, which lead me to using "sfc /scannow"(In elevated command prompt), which threw "Windows Resource Protection could not start the repair service.". I also tried using "DISM /online /cleanup-image /ScanHealth"(and some of the other /cleanup-image commands), which threw "Error: 87

The cleanup-image option is unknown.".

"sfc /scannow" did work in the recovery command prompt, but returned the regular response that something is wrong but it cannot fix it. I think DISM did not work even there.

I tried to use the built-in In-place Installation, but that didn't work as the "Windows 11 Insider Preview Feature Update (28120.3002)" did not get past 0% Downloading and threw "Download error - 0x80040154"

Running the setup.exe of an ISO created using the MediaCreationTool only allowed the clean-install option, due to a mismatched image issue(Which is likely due to the fact that I am on the Insider Dev Channel and the ISO that was created isn't for it), so I tried using two different Insider ISOs from "https://www.microsoft.com/en-us/software-download/windowsinsiderpreviewiso". For comparing:

Current build: 28020.1371
Attempted ISO 1: 28020.2904
Attempted ISO 2: 28120.3002

The first ISO matched my current build version more, but the second ISO was the same as the update which failed to download. Both threw "Windows 11 Installation has Failed" a bit into the installation process started through the setup.exe of each. My PC did not restart at all, although it is supposed to do so multiple times. I have done a clean-boot, checked TPM 2.0, and insured secure boot is not disabled. My reserved partition has 16MB. I have 56.4GB free space.

I have queued for unenrollment from the Insider program, but that shall only take affect with the next major update(26H2), and I would like a sooner option. I also want to avoid a clean install if possible.

Is there anything else that I can try?

0 comments

2 answers

Your answer

Answer 1

Thomas4-N 22,015 Microsoft External Staff Moderator

Hello Jeremy Green,

Since Windows Update is failing, multiple Insider ISOs are failing, SFC is broken, and DISM appears to be malfunctioning, the quickest path may be a clean installation rather than continuing to troubleshoot the existing installation.

Back up any important files, create current Windows 11 installation media, boot from the USB, delete the Windows partitions, and perform a clean install.

At this point there are multiple indicators that the current Windows installation may be sufficiently damaged that repairing it could take longer than rebuilding it.

If the goal is simply to get onto a working Insider build again, a clean installation is likely the most reliable and time-efficient option.

Thomas4-N 22,015 Reputation points Microsoft External Staff Moderator

2026-09-17T06:51:23.24+00:00

Hello Jeremy Green,

Just check in to see how things are going. Let me know if you need anything.

Answer 2

Try the supported Windows repair paths first, then use an in-place repair from matching media if Windows Setup still fails.

Remove anything that commonly blocks upgrade or repair.
- Unplug nonessential hardware such as USB drives, printers, scanners, speakers, and external drives.
- If the device is docked, undock it.
- Uninstall non-Microsoft antivirus or other nonessential software from Control Panel\Programs\Programs and Features.
- For 0xC1900101-class setup failures, Microsoft also recommends checking Device Manager for devices with a yellow exclamation mark and updating or uninstalling the affected driver.
Run Windows repair commands from an elevated Command Prompt.
- Open Command Prompt as administrator.
- Run:
```
     DISM.exe /Online /Cleanup-image /Restorehealth
```
- Wait for the success message.
- Then run:
```
     sfc /scannow
```
- Wait for the scan to reach 100%, then try Windows Update or Setup again.
If Windows Update or Setup is still being blocked, do a clean restart and retry.
- A clean restart starts Windows with a minimal set of drivers and startup programs and can eliminate software conflicts during update or installation.
- This is specifically recommended for setup failures caused by background processes.
If update components appear corrupted, reset the Windows Update folders.
- Warning: these are advanced command-line steps and require administrator permissions.
- In an elevated Command Prompt, 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.
Check and repair disk errors.
- In an elevated Command Prompt, run:
```
     chkdsk /f C:
```
- Restart when prompted so repairs can run.
If DISM still cannot repair the image or Setup keeps failing, use an in-place repair from matching Windows media.
- The documented repair path for persistent corruption is to mount Windows installation media and run setup.exe as an in-place repair/upgrade that keeps files and apps, provided the media matches the installed system closely enough.
- Similar Microsoft Q&A cases with persistent DISM or setup failures were resolved by mounting the recommended ISO and running setup.exe to rebuild system files while preserving personal files and apps.
If matching media still only offers clean install, the remaining documented fallback is a clean installation.
- This is the last resort because it is more disruptive.

Given the current symptoms:

sfc /scannow reporting that the repair service could not start,
DISM failing,
Windows Update failing to download the Insider feature update,
and Setup failing before restart,

the most relevant supported sequence is:

clean restart,
remove third-party security software and nonessential peripherals,
run DISM.exe /Online /Cleanup-image /Restorehealth then sfc /scannow,
reset SoftwareDistribution/Catroot2,
run chkdsk /f C:,
retry the in-place repair from the closest matching ISO.

If the ISO still does not allow keeping files and apps because of image mismatch, the context does not provide a faster supported path to leave Insider builds without using matching repair media or moving to a clean installation.