Missing Method in AppController

You are seeing this error because the action webroot is not defined in controller AppController

If you want to customize this error message, create www.na-sa.com.ar/views/errors/missing_action.thtml.

Fatal: Confirm you have created the AppController::webroot() in file : www.na-sa.com.ar/controllers/app_controller.php

<?php
class AppController extends AppController {
   function webroot() {
   }

}
?>