<code><font color=green>' zunächst die benötigten API-Deklarationen</font>
Private Declare Function SetFocusWnd Lib "user32.dll" Alias "SetFocus" _
  (ByVal hwnd As Long) As Long
 
Private Declare Function SendMessage Lib "user32" Alias _
  "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, _
  ByVal wParam As Long, lParam As Any) As Long
 
Const WM_SYSCOMMAND = &H112
Const SC_CLOSE = &HF060
Const LNULL = 0&
 
<font color=green>' Fenster schließen</font>
SetFocusWnd hwnd
SendMessage hwnd, WM_SYSCOMMAND, SC_CLOSE, LNULL</code>