Fix Windows Update Error Code 0xc1420121 On Windows 10/11

How to Fix Windows Update Error Code 0xc1420121 On Windows 11/10
Step 1) Run Update Troubleshooter
Step 2) Start Windows Update & Background Intelligent Transfer Service
Step 3) Use Windows 10 Update Assistant/ Windows 11 Installation Assistant

Step 4) Reset Windows Update Components
SC config trustedinstaller start=auto
net stop bits
net stop wuauserv
net stop msiserver
net stop cryptsvc
net stop appidsvc
Ren %Systemroot%SoftwareDistribution SoftwareDistribution.old
Ren %Systemroot%System32catroot2 catroot2.old
regsvr32.exe /s atl.dll
regsvr32.exe /s urlmon.dll
regsvr32.exe /s mshtml.dll
netsh winsock reset
netsh winsock reset proxy
rundll32.exe pnpclean.dll,RunDLL_PnpClean /DRIVERS /MAXCLEAN
dism /Online /Cleanup-image /ScanHealth
dism /Online /Cleanup-image /CheckHealth
dism /Online /Cleanup-image /RestoreHealth
dism /Online /Cleanup-image /StartComponentCleanup
Sfc /ScanNow
net start bits
net start wuauserv
net start msiserver
net start cryptsvc
net start appidsvc

Name it Wufix.bat
Right-click on the Wufix file and click Run as administrator
Restart your PC
Step 5) Use Media Creation Tool

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Concluzion: Fix Windows Update Error Code 0xc1420121 On Windows 10/11 – Fix can’t update Windows 10/11 Error Code 0xc1420121,Fix Windows 10/11 Not Updating Error Code 0xc1420121

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