I snagged this helpful alert from

To anyone who has Windows 7!
Microsoft released an update recently for Windows 7: KB2823324, if you haven't installed it already don't, if you have they're advising you to uninstall it immediately. It's buggy and can cause your computer to not boot. Here are some ways to get rid of it:
TO UNINSTALL IT IF YOU HAVEN'T FALLEN VICTIM TO THE BUGS:
go to Control Panel > Programs
Under programs and features go to View Installed Updates.
search for "KB2823324" (make sure KB is in there, otherwise it won't be recognized)
uninstall it and restart your computer.
TO UNINSTALL IT IF YOU HAVE FALLEN VICTIM TO THE BUGS:
restart your computer by pressing the F8 key
select Repair Your Computer; select language and log on
select System Restore
start up your computer normally. Doing this should uninstall KB2823324.
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