Missing Controller

Error: AO.htmlController could not be found.

Error: Create the class AO.htmlController below in file: app\controllers\a_o.html_controller.php

<?php
class AO.htmlController extends AppController {

	var $name = 'AO.html';
}
?>

Notice: If you want to customize this error message, create app\views\errors\missing_controller.ctp