In case if a service tries to run an application which shows GUI, that GUI will be shown in session 0(that applies only to Win-8)
It's possible to see what's happening in that mysterious 0 session, by following these steps:
1. Enable Interactive sessions:
Hive: HKLM
Path: SYSTEM\CurrentControlSet\Control\Windows
DWORD: NoInteractiveServices
Change value from 1 to 0
2. Go to services and enable - Interactive Services Detection service.
Now you can run any application in 0 session for testing:
psexec -i 0 calc.exe
Such a popup should appear, and if you press "View the message" you will be directed to the new session:
It's possible to see what's happening in that mysterious 0 session, by following these steps:
1. Enable Interactive sessions:
Hive: HKLM
Path: SYSTEM\CurrentControlSet\Control\Windows
DWORD: NoInteractiveServices
Change value from 1 to 0
2. Go to services and enable - Interactive Services Detection service.
Now you can run any application in 0 session for testing:
psexec -i 0 calc.exe
Such a popup should appear, and if you press "View the message" you will be directed to the new session: