交流 scandir() has been disabled for security reasons

安装出现问题，请问怎么解决

Server Error
scandir() has been disabled for security reasons

1. XenForo_Application::handlePhpError()
2. scandir() in XenForo/Install/Model/Install.php at line 100
3. XenForo_Install_Model_Install->getRequirementErrors() in XenForo/Install/Controller/Install.php at line 18
4. XenForo_Install_Controller_Install->actionIndex() in XenForo/FrontController.php at line 351
5. XenForo_FrontController->dispatch() in XenForo/FrontController.php at line 134
6. XenForo_FrontController->run() in /home/wwwroot/www.mortartech.com/install/index.php at line 18