Dim pfad As String = My.Application.Info.AssemblyName & ".ico"
  Using b As New Bitmap(16, 16), g As Graphics = Graphics.FromImage(b)
   g.Clear(Color.Yellow)
   g.DrawString("X", New Font("Arial", 14, FontStyle.Bold Or FontStyle.Italic, _
     GraphicsUnit.Pixel), Brushes.Black, 0, 0)
    Using fs As New IO.FileStream(pfad, IO.FileMode.Create)
         Drawing.Icon.FromHandle(b.GetHicon).Save(fs)
    End Using
  End Using
  If System.IO.File.Exists(pfad) Then
     Me.Icon = New Icon(pfad)
  End If