A screen shot is attached.Also Posted the issue in http://answers.microsoft.com/en-us/windows/forum/windows_10-performance/windows-10-freezes-at-sometimes-no-app-and-taskbar/aa506bb2-f54b-4007-bb3c-ca4604cb5842 Microsoft Support page
Wat OS/SP ?
What exact version of avast ?
Any other security (related) software installed ? (or was there)
Already performed a repair of avast ?
Already performed a clean installation of the latest avast ?
What was the file that you tried to open ??? This sounds like a file association problem.
What makes you think it has something to do with Avast ???