Dim conn As New OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0; ..."
        Dim SQL As String = "INSERT INTO [tbl_belegnr] VALUES (@p1, ...)"
        Dim cmd As New OleDbCommand(SQL, conn)
        Dim p1 As OleDbParameter = cmd.Parameters.Add("p1", OleDbType.Integer)
        'Dim p2 ....
 
        Dim cnt As Integer
 
        Try
            conn.Open()
            Do While '...
                '...
                p1.Value = belegnr_belegnr
                cnt = cmd.ExecuteNonQuery()
            Loop
 
        Catch ex As Exception
            MsgBox(ex.ToString())
 
        Finally
            conn.Close()
        End Try

Those people who think they know everything are a great annoyance to those of us who do - Isaac Asimov