Windows Update

Kyle Hemingway 0 Reputation points
2026-07-28T15:16:21.4733333+00:00

my windows update will not get past 35% and then says error and undoing changes. this is for business

Windows for business | Windows Client for IT Pros | Devices and deployment | Install Windows updates, features, or roles
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  1. Brian Huynh 3,650 Reputation points Microsoft External Staff Moderator
    2026-07-29T02:13:10.2733333+00:00

    Hello Kyle Hemingway, thank you for posting in the Microsoft Q&A community.

    This behavior is typically triggered by a corrupted Windows Update cache, missing or corrupted system files, a driver conflict during the update application phase, or interference from third-party endpoint security software preventing the system from modifying protected directories.

    Please clear any potentially corrupted update files and ensure system health:

    1. Clear the Windows Update Cache

    Open Command Prompt as an Administrator and run the following commands one by one to stop the update services, clear the cache, and restart the services:

    
    net stop wuauserv
    
    net stop cryptSvc
    
    net stop bits
    
    net stop msiserver
    
    ren C:\Windows\SoftwareDistribution SoftwareDistribution.old
    
    ren C:\Windows\System32\catroot2 catroot2.old
    
    net start wuauserv
    
    net start cryptSvc
    
    net start bits
    
    net start msiserver
    
    

    Once the commands have been executed successfully, restart the computer and attempt the Windows Update again.

    2. Repair System Files using DISM and SFC

    Open Command Prompt as an Administrator and execute these commands in order, waiting for each to complete 100%:

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

    If the update still fails after trying the above steps, I will need a bit more data to pinpoint the exact point of failure. Could you please provide the following details?

    • What is the specific Error Code shown in the Windows Update history? You can find this by navigating to Settings > Update & Security > Windows Update > View update history.
    • Are you running any third-party antivirus, disk encryption, or endpoint protection software? If so, consider temporarily disabling it during the update process.

    If you are comfortable grabbing logs, we can identify the exact driver or file causing the rollback. Please check the Component Based Servicing log located at C:\Windows\Logs\CBS\CBS.log for errors that occurred right when the update hit 35%.

    I will follow up on this thread to ensure your issue is resolved. If this information helps clarify the behavior, please consider clicking "Accept Answer" so that other community members can benefit from it.

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