How to load view in file error_404.php?

[eluser]Unknown[/eluser]
In 'application/config/routes.php' just specify the controller and function to be called on a 404.

routes.php
----------

Code:

$route['404_override'] = 'site/not_found';

Using the above example just put a function called 'not_found' in the controller 'site.php'.
Then just load the view you want as usual.

site.php
--------

Code:

public function not_found()
{
$this->load->view('error_404');
}