Windows Defender KB4052623 (Version 4.18.1905.4) repeated installation fail with Error 0x80070643

[Guest suirauqa]

Can someone please tell me more about this situation? This Windows Defender update is repeatedly failing to install: KB4052623 (Version 4.18.1905.4) installation fail with Error 0x80070643. I have searched various forums for a solution, but have found none so far.

 

 

When I try to update Windows Defender from within Windows Defender, I get another error message saying: error code -2147023293 protection definition update failed.

 

 

Thanks in advance for any help provided. Here are the respective screenshots of the error messages:

 

 

 

Oh, and I should add that there are no other 3rd party antivirus/antimalware programs installed on this computer.

 

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