Hi, I need to prevent monitor off and screensaver activation while my script is running. After a research, i need to intercept $SC_SCREENSAVE and $SC_MONITORPOWER This is what i have done: #include <GUIConstantsEx.au3> Global Const $WM_SYSCOMMAND = 0x112; Global Const $SC_MONITORPOWER = 0xF170; Global Const $SC_SCREENSAVE = 0xF140; GUICreate("Test") GUISetState(@SW_SHOW) GUIRegisterMsg($WM_SYSCOMMAND,"WM_SYSCOMMAND") While 1 $msg = GUIGetMsg() If $msg = $GUI_EVENT_CLOSE