CodeIgniter can't find CI_Controller

I'm trying to get CodeIgniter running on my testserver (using XAMPP). I have set up everything like i usually do, plus I've copied all of the files from a working installation on my web server and just chan开发者_JAVA百科ged the necessary config options:

1. Fatal error: Class 'CI_Controller' not found in D:\Websites\****\www\application\controllers\main.php on line 4

2. Message: Undefined index: scaffolding_trigger, Filename: libraries/Router.php

I'm pretty sure my controller is set-up properly, but in case it isn't here's the setup:

class Speaker extends CI_Controller
{
     function __construct()
     {
         parent::__construct();
         $this->load->helper('url');
     }
}

Anyone know what I'm doing wrong here?

Gah I hate how you finally find the problem right as you ask the question haha

I decided to check out my system folder and found it was out of sync with what I had on my server. Just updated it and everything's working.

You only extend CI_Controller if you are using CodeIgniter 2.0.x as 1.7.x extends Controller.