Error Code: 66A (Can't install KB2160841)

I am receiving "Error code 0000066A Windows Update encountered an unknown error" when Windows Update fails 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). I have tried to manually install the update and it is blocked from installing. I then have tried to uninstall .NET Framework 4 and reinstall it, and that fails as well. I cannot uninstall .NET Framework 4 and I cannot reinstall or update it. What is the solution?


Question Info

Last updated May 9, 2019 Views 38,059 Applies to:


Try the following steps, please:

1.    Go to Program and Features, click it.

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

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

4.    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.

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

My PC was able to update the Microsoft.Net Framework 4 Client Profile, after performing the steps.  Reboot your PC.  I re-scanned with Secunia Personal Software Inspector and everything in my PC was up to date.

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