[Solved] Win8.1 hangs on shutdown with Avast 2015 free

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Today I installed the patches from Microsoft together with Avast2015 Free.When I decided to reboot the PC it got stuck in either shutdown, please wait or Restart.

I read an article that stated that Avast 2015 was not compatible with the optional KB3000850.
After uninstalling this patch Avast did run without issues.

Update:
Avast has solved the issue. Before installing KB3000850 you should check if
C:\Windows\System32\drivers\aswsnx.sys should has a higher version than 1.0.2208.712
So check this version before installing this Microsoft update