Private Sub ZeitenDataGridView_DragEnter(ByVal sender As Object, ByVal e As _
  System.Windows.Forms.DragEventArgs) Handles ZeitenDataGridView.DragEnter
        Dim cp = Cursor.Position
        Dim pt = ZeitenDataGridView.PointToScreen( _
          ZeitenDataGridView.GetCellDisplayRectangle(1, _
          ZeitenDataGridView.Rows.Count - 1, True).Location)
        pt.Y += ZeitenDataGridView.RowTemplate.Height
        If cp.Y < pt.Y Then
            e.Effect = DragDropEffects.None
        ElseIf cp.Y > pt.Y AndAlso cp.X > pt.X AndAlso _
          e.Data.GetDataPresent(DataFormats.StringFormat, True) Then
            e.Effect = DragDropEffects.All
        End If
    End Sub

Danke für die Hilfe

Gruß Christian