how to fix 'The Windows Update diagnostic failed to run'

Helen Featherstone 60 Reputation points
2026-06-03T18:19:45.2033333+00:00

how to fix 'The Windows Update diagnostic failed to run'

Windows for home | Windows 11 | Windows update

Locked Question. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.

4 answers

Sort by: Newest
  1. Deleted

    This answer has been deleted due to a violation of our Code of Conduct. The answer was manually reported or identified through automated detection before action was taken. Please refer to our Code of Conduct for more information.


    Comments have been turned off. Learn more

  2. Deleted

    This answer has been deleted due to a violation of our Code of Conduct. The answer was manually reported or identified through automated detection before action was taken. Please refer to our Code of Conduct for more information.


    Comments have been turned off. Learn more

  3. Lester Bernard Reyes 85,335 Reputation points Independent Advisor
    2026-06-03T19:11:30.66+00:00

    Hi, I'm Bernard. I'm happy to help!

    Kindly follow the steps below the steps provided by AI answer. However, if the issue persists, I suggest doing an in-place upgrade, wherein it will upgrade the device to the latest version and repair all issues without deleting any files.

    Go to the Windows 11 website: https://www.microsoft.com/en-us/software-download/windows11

    Under Download Windows 11 Disk Image (ISO), select Windows 11 (multi-edition ISO)

    1. Once done downloading the ISO, kindly right-click on the ISO, then click Mount> click Setup.exe
    2. You may be prompted by User Account Control. Click on Yes if so
    3. In the Install Windows 11 dialog, click Next
    4. Setup will check your PC and show a license agreement. Click on Accept in the license terms dialog.
    5. Wait for the setup program to check for the available free space.
    6. On the Ready to install page, make sure Keep personal files and apps have been checked.
    7. Then click Install and just follow the prompt.
    8. Windows 11 will restart your device several times and lead you to the lock screen. Depending on the options you set, it will keep all your files, apps, and user accounts.

    Note: This is a public forum. I may respond shortly, but I apologize in advance for any delays. I am simply a fellow user trying to provide helpful insights and information.

    Was this answer helpful?

    20+ people found this answer helpful.
  4. AI answer

    2026-06-03T18:20:06.0166667+00:00

    Use the built-in Windows 11 tools and general Windows Update repair steps to work around the failed diagnostic.

    1. Run the Windows Update troubleshooter from Settings
      1. Select Start > Settings > System.
      2. Select Troubleshoot > Other troubleshooters.
      3. Find Windows Update and select Run.
      4. Follow the on‑screen instructions.
      If available on the device, also run the automated troubleshooter in the Get Help app using the Windows Update troubleshooter entry.
    2. Repair Windows system files (DISM and SFC)
      1. In the search box on the taskbar, type command prompt.
      2. Select Run as administrator.
      3. Run:
              DISM.exe /Online /Cleanup-image /Restorehealth
        
        Wait for it to complete successfully.
      4. Then run:
              sfc /scannow
        
        Wait until verification reaches 100%, then close Command Prompt.
      5. Try Windows Update again and re‑run the Windows Update troubleshooter from Settings if needed.
    3. Reset Windows Update components If the troubleshooter still fails or Windows Update continues to have issues, reset the SoftwareDistribution and Catroot2 folders:
      1. Open Command Prompt as administrator.
      2. Run these commands one by one, pressing Enter after each and waiting for completion:
              net stop bits
              net stop wuauserv
              ren %systemroot%\softwaredistribution softwaredistribution.bak
              ren %systemroot%\system32\catroot2 catroot2.bak
              net start bits
              net start wuauserv
        
      3. Restart the PC and try Windows Update again.
    4. Run a disk check if corruption is suspected
      1. Open Command Prompt as administrator.
      2. Run:
              chkdsk /f C:
        
      3. Approve running at next restart if prompted, then restart so repairs can run.
    5. As a last resort, perform a repair/clean installation If Windows Update and its diagnostic tools still fail after the above steps, back up personal files and consider a repair or clean installation of Windows 11 using the official installation media or tools referenced in the Windows Update troubleshooting documentation.

    References:

    AI-generated content may be incorrect. Read our transparency notes for more information.

    Was this answer helpful?

    50+ people found this answer helpful.