Using dlg As New OpenFileDialog With {.Title = "Titel", _
                                              .Multiselect = False, _
                                              .RestoreDirectory = True, _
                                              .Filter = "Alle Dateien (" & _
                                              "*.*)|*.*"}
            If dlg.ShowDialog = Windows.Forms.DialogResult.OK Then
                ' Datei öffnen
                Process.Start(dlg.FileName) 
            End If
        End Using