Windows 7 Home Premium with Norton 360 v2 installed.
After installed free software downloaded from internet, my system happened to have pop up Windows Security box.
When I tried to run eg. .exe this box came up.
Please see attached file of the screen snapshot.
I have also run MalwareByte Anti-Malware, it deleted 7 infected objects in the first run.
Reboot my pc and re-scan with it, no infected objects found. But this warning box still came up.