G app is preventing from restarting

Each time I want to shutdown or restart the computer I get this annoying message.
How do I get rid of it?

Callender said:

Kill hanging apps:

Shutdown time

You'd better check your running processes and see if you can identify the app.

Looks like a lot of apps running as G,but none of them are viruses,malware,those are known apps...
I can't shut them off,because I need them.
It seems that it is linked to some DLL in WinSxS folder...still dunno how to get rid of it...


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It’s a bug in the way the Blocked Shutdown Resolver pulls the name of the program blocking a shutdown, and “G” may result when there’s a GDI+ program (a program that draws stuff on the screen) that turns belly up as you’re shutting down.
source:
Mysterious app keeps you from shutting down — or does it? | Computerworld