Private Sub Form_Unload(Cancel As Integer)
  Dim Antwort As String
 
  Antwort = MsgBox("Wollen Sie wirklich das Programm beenden?", _
    vbExclamation + vbYesNo, "ACHTUNG!")
 
  If Antwort = vbNo Then
    Exit Sub
  ElseIf Antwort = vbYes Then
    EndAll
  End If
End Sub

Public Sub EndAll()
Dim frm As Form
 
For Each frm In VB.Forms
    unload frm
    Set frm = Nothing
Next frm
 
End Sub