Hi Youssef,

In addition to Raymond's response you can also create and apply a feature control for Android+ devices which disables the use of Multi-Window on both Samsung ELM and non ELM devices. 

Your device seems to be a Samsung device.   If so, you have at least 2 options:

1. There should be a  "Multi Window" option in your device "Settings" to enable/disable. 

2   You can try disabling it remotely  by sending the following script :

  writesecuresetting -sys multi_window_enabled 0
  writesecuresetting -sys multi_window_expanded 0

Thanks Chan for your return, 

The script you sent me it works fine.

Hi,

Thanks for your helpful.