Fix Windows KB5004945 Update Error – Windows 10, Windows 11 2026

Start with the built-in troubleshooter to automatically detect and fix common update issues:

1. Press Windows + I to open Settings
2. Navigate to Update & Security → Troubleshoot → Additional troubleshooters
3. Click Windows Update and select Run the troubleshooter
4. Follow the on-screen prompts and apply any recommended fixes
5. After completion, open Command Prompt as administrator
6. Run the System File Checker scan:

sfc /scannow

Wait for the scan to complete (typically 15-30 minutes). If corrupted files are found and repaired, restart your computer.

Verification: Go to Settings → Update & Security → Windows Update and click Check for updates. KB5004945 should now install successfully.

Manually reset all Windows Update services and clear the update cache:

1. Open Command Prompt as administrator
2. Stop Windows Update services:

net stop wuauserv
net stop cryptSvc
net stop bits
net stop msiserver

3. Rename the SoftwareDistribution and catroot2 folders:

ren C:\Windows\SoftwareDistribution SoftwareDistribution.old
ren C:\Windows\System32\catroot2 catroot2.old

4. Restart the Windows Update services:

net start wuauserv
net start cryptSvc
net start bits
net start msiserver

5. Clear the Windows Update cache completely:

dism /online /cleanup-image /startcomponentcleanup

Verification: Restart your computer and check Windows Update. The KB5004945 update should appear and install without errors.

Repair the Windows system image using the Deployment Image Servicing and Management tool:

1. Open Command Prompt as administrator
2. Check the current image health:

dism /online /cleanup-image /checkhealth

3. Scan for component store corruption:

dism /online /cleanup-image /scanhealth

4. If corruption is detected, repair the image:

dism /online /cleanup-image /restorehealth

5. After DISM completes successfully, run SFC again:

sfc /scannow

6. Clear the Windows Update cache:

wsreset.exe

Verification: Restart the system and attempt to install KB5004945 through Windows Update. The update should now proceed without component-related errors.

Download and install KB5004945 manually when automatic installation fails:

1. Visit the Microsoft Update Catalog website
2. Search for "KB5004945" in the search box
3. Identify the correct version for your system architecture (x64, x86, or ARM64)
4. Download the appropriate .msu file to your Downloads folder
5. Before installation, ensure sufficient disk space (at least 10GB free)
6. Right-click the downloaded .msu file and select Install
7. Alternatively, install via Command Prompt:

wusa.exe "C:\Users\%USERNAME%\Downloads\windows10.0-kb5004945-x64.msu" /quiet /norestart

8. Monitor the installation progress in the Command Prompt window
9. If installation fails, try the standalone installer method:

dism /online /add-package /packagepath:"C:\Users\%USERNAME%\Downloads\windows10.0-kb5004945-x64.msu"

Verification: Check installed updates in Settings → Update & Security → View update history. KB5004945 should appear in the successfully installed updates list.

Perform advanced registry cleanup and service configuration when other methods fail:

1. Create a system restore point before proceeding
2. Open Registry Editor (regedit.exe) as administrator
3. Navigate to the Windows Update registry key:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\WindowsUpdate

4. Delete the following subkeys if they exist:

• Auto Update
• RebootRequired
• PostRebootReporting

5. Navigate to the AU registry location:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\WindowsUpdate\Auto Update

6. Delete the entire Auto Update key if present
7. Reset Windows Update Agent using PowerShell:

Get-Service -Name wuauserv | Stop-Service -Force
Remove-Item -Path "C:\Windows\SoftwareDistribution" -Recurse -Force
Get-Service -Name wuauserv | Start-Service

8. Re-register Windows Update DLL files:

regsvr32 /s atl.dll
regsvr32 /s urlmon.dll
regsvr32 /s mshtml.dll
regsvr32 /s shdocvw.dll
regsvr32 /s browseui.dll
regsvr32 /s jscript.dll
regsvr32 /s vbscript.dll
regsvr32 /s scrrun.dll
regsvr32 /s msxml.dll
regsvr32 /s msxml3.dll
regsvr32 /s msxml6.dll
regsvr32 /s actxprxy.dll
regsvr32 /s softpub.dll
regsvr32 /s wintrust.dll
regsvr32 /s dssenh.dll
regsvr32 /s rsaenh.dll
regsvr32 /s gpkcsp.dll
regsvr32 /s sccbase.dll
regsvr32 /s slbcsp.dll
regsvr32 /s cryptdlg.dll

Verification: Restart the computer and run Windows Update. KB5004945 should install successfully after the comprehensive cleanup and re-registration process.