Windows update is always failing with error code 0x80070643 and Defender stopped working after this

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Occasional Visitor

I received a suggestion to download -

"Update for Microsoft Defender Antivirus antimalware platform - KB4052623 (Version 4.18.2105.3)"

 

and I updated it through Windows Update platform. But it resulted in -

 

"Status: Download error 0x80070643"

There were some problems installing updates, but we'll try again later. If you keep seeing this and want to search the web or contact support for information, this may help: (0x80070643)

 

After this my Microsoft Defender Antivirus Threat service is stopped and not working ever since (restarting the service results in error also).

 

Please help!

 

1 Reply

Hello @imanojpatel

 

Please run Windows Update troubleshooter from Settings app > Update & security > Troubleshoot > Additional troubleshooters. See if it works.

 

If that doesn't work, try this:

 

Open administrative Command Prompt and type following commands one-by-one followed by Enter key.

 

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

 

Close Command Prompt and see if Windows Updates works then.

 

Let us know if this helps!