dg_mask.Columns.RemoveAt(dg_mask.Columns("Typ").Index)
Dim co As New DataGridViewComboBoxColumn
co.Name = "Typ"
co.DataSource = createTypTbl()
co.DataPropertyName = "Typ"
co.ValueMember = "T"
co.DisplayMember = "T"
co.HeaderText = "typ"
co.DisplayIndex = 8
co.Width = 40
dg_mask.Columns.Add(co)

 Private Function createTypTbl() As DataTable
 
        Dim dt As New DataTable("Typ")
        dt.Columns.Add("T", GetType(System.String))
        'dt.Columns.Add("B", GetType(System.String))
 
        Dim MA() As String = {"K", "O", "U", "I", "R", "M"}
 
        For i As Integer = 1 To 6
            dt.Rows.Add(dt.NewRow())
            dt.Rows(i - 1)(0) = MA(i - 1)
        Next
 
        Return dt
    End Function