Public Sub DGunsel()
        'alle Datensätze demarkieren
        Dim i As Integer
        For i = 0 To DV1.Count
            DataGrid1.UnSelect(i)
        Next i
    End Sub

Public Sub DGsel()
        'alle Datensätze werden markiert
        Dim i As Integer
        For i = 0 To DV1.Count
            DataGrid1.Select(i)
        Next i
    End Sub

Private Sub Button14_Click(ByVal sender As System.Object, ByVal e As _
  System.EventArgs) Handles Button14.Click
        'Rücksetzen der RadioButtons
        RadioButton8.Checked = False
        RadioButton9.Checked = False
        RadioButton10.Checked = False
        'DataGrid wird demarkiert
        DGunsel()
    End Sub

VB@rchiv its the Best