Dim werte As List(Of String) = From r As DataGridViewRow In _
              dgv.Rows.Cast(Of DataGridViewRow)() _
                                           Order By CStr(IIf(IsDBNull(r.Cells( _
                                           "UE80_1BEZ").Value), " ", r.Cells( _
                                           "UE80_1BEZ").Value)) _
                                           Select CStr(IIf(IsDBNull(r.Cells( _
                                           "UE80_1BEZ").Value), " ", r.Cells( _
                                           "UE80_1BEZ").Value)) Distinct.ToList( _
                                           )
            Dim co As New DataGridViewComboBoxColumn
            With co
                .Name = "UE80_1BEZ"
                .DataPropertyName = "UE80_1BEZ"
                .DataSource = werte
                .HeaderText = "UE80_1BEZ"
                .DisplayIndex = dgv.Columns("UE80_1BEZ").DisplayIndex
            End With
            dgv.Columns.Add(co)
            dgv.Columns.RemoveAt(dgv.Columns("UE80_1BEZ").Index)

    Private Sub dgv_Edit(ByVal sender As System.Object, ByVal e As _
      System.Windows.Forms.DataGridViewCellCancelEventArgs) Handles _
      dgv.CellBeginEdit
        Dim titel As String = dgv.Columns(e.ColumnIndex).HeaderText
        If (titel.Equals("PRODUKTGRUPPE")) Then
            Dim wert As String = dgv.Rows(e.RowIndex).Cells(e.ColumnIndex).Value
            'Comboboxen
            Dim werte As List(Of String) = From r As DataGridViewRow In _
              dgv.Rows.Cast(Of DataGridViewRow)() _
                                           Order By CStr(IIf(IsDBNull(r.Cells( _
                                           titel).Value), " ", r.Cells( _
                                           titel).Value)) _
                                           Select CStr(IIf(IsDBNull(r.Cells( _
                                           titel).Value), " ", r.Cells( _
                                           titel).Value)) Distinct.ToList()
            Dim co As New DataGridViewComboBoxCell
            With co
                .DataSource = werte
                .Value = wert
            End With
            dgv.Rows(e.RowIndex).Cells(e.ColumnIndex).???
            dgv.Item(e.ColumnIndex, e.RowIndex).???
        End If
    End Sub