View file upload/admin.php

<?php

$startTime = microtime(true);
$fileDir = dirname(__FILE__);

require($fileDir . '/library/XenForo/Autoloader.php');
XenForo_Autoloader::getInstance()->setupAutoloader($fileDir . '/library');

XenForo_Application::initialize($fileDir . '/library', $fileDir);
XenForo_Application::set('page_start_time', $startTime);

$fc = new XenForo_FrontController(new XenForo_Dependencies_Admin());
$fc->run();