#include <ButtonConstants.au3>
#include <GUIConstantsEx.au3>
$Form1 = GUICreate("Form1", 283, 106, 192, 124)
$Checkbox1 = GUICtrlCreateCheckbox("Checkbox1", 24, 56, 97, 17)
$Button1 = GUICtrlCreateButton("Button1", 152, 56, 75, 25)
GUISetState(@SW_SHOW)
While 1
$nMsg = GUIGetMsg()
Switch $nMsg
Case $GUI_EVENT_CLOSE
Exit
Case $Button1
GUICtrlSetState($Checkbox1,$GUI_UNCHECKED)
EndSwitch
WEnd