From Andre Kittler…
MS just broke Windows 7 on Brazil. Yesterday I had 5 or 6 calls, but my fear if for today, after all my clients shutdown their computer at the end of day.
After this update the OS wont boot, and the better phone-fix is to try a system restore on WinRE.
Now idea how big this is since there is nothing from Microsoft (my guess is at leat 20% of the x86 PT.BR Windows 7 – but I’m a optimist ).
Never do automatic update. Not even on clients.
KB2839011 Released to Address Security Bulletin Update Issue – MSRC – Site Home – TechNet Blogs: