Hello LD,
This error is actually caused by an issue with .NET Framework 4. You can resolve the issue by doing a repair of .NET Framework 4. See this KB article on how that’s done.
Thanks
Bobby
Windows Update error 0x8007066A or 66A
![](data:image/svg+xml, %3Csvg xmlns='http://www.w3.org/2000/svg' height='64' class='font-weight-bold' style='font: 600 30.11764705882353px "SegoeUI", Arial' width='64'%3E%3Ccircle fill='hsl(128, 8%, 22%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EA%3C/text%3E%3C/svg%3E)
Anonymous
Hello,
I get Windows Update error “0x8007066A” or “66A” when installing updates using Windows Update or Microsoft Update, Is this a known issue? How do I fix this?
Thanks
Windows for home | Windows 10 | Install and upgrade
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Anonymous
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Anonymous
2011-12-01T05:43:15+00:00 HELP! Is there anyone out there to help resolve these error codes? I don't have my new printer installed, so the long lists of suggestions don't help! Thanks!
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Anonymous
2011-12-01T05:41:40+00:00 HELP! Is there anyone out there to help resolve these error codes? I don't have my new printer installed, so the long lists of suggestions don't help! Thanks!
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Anonymous
2011-11-29T17:19:35+00:00 I also am having this issue of Code 66A with the following updates: KB2478663, KB2487367, KB2518870, KB2468871, and KB2533523 on Windows Server 2008 R2 Standard Service Pack 1.
I have tried the Repair as mentioned and the repair does not complete successfully, actually the following occurs: .NET Framework 4 Client Profile has not been repaired because: Fatal error during installation.
There is also a log file for this, however, I am unsure as to whether I should place the details of that in here or not.
Please help as this causing all updates to .NET framework 4 to fail.
Thanks.