Windows 7 - Error Code: 66a (Can't install KB2160841)

Anonymous
2010-10-17T21:56:37+00:00

Getting error code 66A Windows update encountered an unknown error. 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)

Installation date: ‎10/‎17/‎2010 2:14 PM

Installation status: Failed

Error details: Code 66A

Update type: Important

A security issue has been identified that could allow an attacker to compromise your Windows-based system that is running the Microsoft .NET Framework and gain complete control over it. You can help protect your computer by installing this update from Microsoft. After you install this item, you may have to restart your computer.

Windows for home | Previous Windows versions | Windows update

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Anonymous
2013-11-18T11:58:38+00:00

Frank's solution didn't work for me too.

But i solved it by uninstalling the .net framework extended and left the .net client on the server.

Update worked after that and the extended component came back with the latest updates.

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Anonymous
2010-10-27T18:34:29+00:00

had same problem,for a week,go to control panel click uninstall programs,find >Net framework 4 client profile file ,then click right and do repair file ,install part worked fine right after

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  1. Anonymous
    2016-12-22T21:55:26+00:00

    A slightly different fix worked for me when I received "Error Code: 66a" when I tried to install KB3205402:

    1.  I turned off recommended updates after Microsoft's borderline-deceptive attempts to upgrade everyone to Windows 10.  BTW, I love Windows 10, but too many of my clients had to hire me to uninstall the free Windows 10 upgrade.

    2.  I installed recommended update KB3102433 - Microsoft .NET Framework 4.6.1 for Windows 7.

    3.  After that, I installed KB3205402 and everything worked fine.

    Mike Honeycutt

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  2. Anonymous
    2015-07-03T06:10:10+00:00

    Thank you, this worked for me, except that I only repaired it and did not uninstall it. I restarted my computer after the repair, did the windows updates, and they worked :)

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