Error Code: 66A (Can't install .Net Framework 4 KB2160841)

tried to install Security Update for .NET Framework 4 on Windows XP, Windows Server 2003, Windows Vista, Windows 7, Windows Server 2008, Windows Server 2008 R2 for x64-based Systems (KB2160841)
And I got the error code 66A I run Avg is this the issue



Question Info

Last updated July 15, 2019 Views 45,180 Applies to:

Hi Pokerbass,


  • Are you able to install other updates without this error message?


Step 1


You may follow the steps below and check if it helps you fix the update installation issue.


A.    Click on Start and click on Control panel.

B.    Go to Program and Features.

C.    Scroll down to Microsoft.Net Framework 4 Client Profile, right click it.

D.   It will give you a choice of Uninstall/Change, click it.

E.    Then, it will give a choice to Repair it, pick Repair  it.  It will take about 4-10 minutes to repair (with my PC) your experience may vary.

F.     When completed, go to your update center, and update it again.


Step 2


If the above steps do not help, access the link below and follow the steps in the article and try to uninstall all the versions of the .NET Framework on the computer, and then reinstall all the versions of the .NET Framework on the computer.


Hope this helps. Let us know the result.


Thanks and Regards,


Srinivas R

Microsoft Support.

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