AU3 # Prevent Script from System Poweroff

preventShutdow.au3

;RUNGUI() ; Remove ';' from first line , so script GUI will open

Func RUNGUI()
$WM_QUERYENDSESSION2 = 0x11
GUIRegisterMsg($WM_QUERYENDSESSION2, "Cancel_Shutdown")
$Hwnd = GUICreate("PreventShutdownGUI")
GUISetSTate(@SW_SHOW)

MsgBox(262144,'','Hello kitty')
_ShutdownBlockReasonCreate($hwnd, "Please Save your work then shut ur pc down :)"&@CR&"secound line goes here")
TrayTip("Shutdown", "Denied shutdown for 15 seconds", 10)
Sleep(30000)
_ShutdownBlockReasonDestroy($hwnd)
EndFunc

Func _ShutdownBlockReasonCreate($Hwnd, $wStr)
    ; http://msdn.microsoft.com/en-us/library/ms...28VS.85%29.aspx
    ; Prog@ndy
    Local $aResult = DllCall("User32.dll", "int", "ShutdownBlockReasonCreate", "hwnd", $Hwnd, "wstr", $wStr)
    If @error Then Return SetError(1,0,0)
    Return $aResult[0]
EndFunc

Func _ShutdownBlockReasonDestroy($Hwnd)
    Local $aResult = DllCall("User32.dll", "int", "ShutdownBlockReasonDestroy", "hwnd", $Hwnd)
    If @error Then Return SetError(1,0,0)
    Return $aResult[0]
EndFunc

Func Cancel_Shutdown($hWndGUI, $MsgID, $WParam, $LParam)
    ; This HAS to be here to capture the endsession...
    ; DO NOT ADD A MSGBOX HERE
    ; Windows shows a not responding box after ~5 secs and allows to kill your app.
    Return False
EndFunc