A PHP Error was encountered

Severity: Warning

Message: call_user_func_array() expects parameter 1 to be a valid callback, class 'Index' does not have a method 'index_404'

Filename: core/CodeIgniter.php

Line Number: 514

Backtrace:

File: /home/duclan/public_html/kythuatduclan/index.php
Line: 315
Function: require_once