“After installing Windows 7 Service Pack 1 (SP1), you might receive the following error message on a blue screen:
"Error C000009A applying update operation {###} of {###} (\Registry...)"
To resolve this issue, restore your computer to a point in time before you installed Windows 7 SP1, uninstall any unused language packs, and then reinstall SP1. To restore your computer to a previous point in time, you'll need to use the System Recovery Options menu.”
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