Private Sub Form_PlanningGuide_FormClosing(sender As Object, e As _
  System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing
 
        My.Settings.InVisibleColumns = ""
 
        Dim stb As New System.Text.StringBuilder
        With Me.BCHHDataGridView
            For i As Integer = 0 To .Columns.Count - 1
                With .Columns(i)
                    If Not .Visible Then
                        stb.Append(.Name & ";")
                    End If
                End With
            Next i
        End With
 
        'Speichern
        My.Settings.InVisibleColumns = stb.ToString
        My.Settings.Save()
 
    End Sub