Fail on cf7_abd.class.php

The problem is that we are using php 5.2,

Can you support php 5.2 (minimum requisite for wordpress)? In this case I had to change your cf7AdbExportController code to no use anonymous functions:

Modifying cf7_adb.class.php :

function empty_function ()      {
        }

        function add_header_function()  {
                        $id= $_GET['id'];
                        $filename = "contact_form_advanced_database_" . date('Ymd') . ".csv";
                        header("Content-Disposition: attachment; filename=\"$filename\"");
                        header("Content-Type: application/vnd.ms-excel");

                        require_once('display/export.php');

                exit;
        }

        function cf7AdbExportController() {
          // filename for download\
          //    $hook = add_submenu_page(null, '', '', 'administrator', 'cf7-adb-export-xls', function(){});
                $hook = add_submenu_page(null, '', '', 'administrator', 'cf7-adb-export-xls', 'empty_function');
                add_action('load-' . $hook, 'add_header_function' );

        }

Thank you very much