Private Declare Function GetClassLong Lib "user32" _
   Alias "GetClassLongA" ( _
   ByVal hwnd As IntPtr, _
   ByVal nIndex As Integer) As Integer
 
    Private Declare Function SetClassLong Lib "user32" _
      Alias "SetClassLongA" ( _
      ByVal hwnd As IntPtr, _
      ByVal nIndex As Integer, _
      ByVal dwNewLong As Integer) As Integer
 
    Private Const GCL_STYLE = (-26)
    Private Const CS_DROPSHADOW = &H20000
 
 
    ' Fenster mit zusätzlichem Schatten ausstatten
    Public Sub SetWindowShadow(ByVal hwnd)
 
        SetClassLong(hWnd, GCL_STYLE, GetClassLong(hWnd, GCL_STYLE) Or _
          CS_DROPSHADOW)
 
    End Sub

        SetWindowShadow(Me)