An uncaught Exception was encountered

Type: Error

Message: Call to a member function category_by_id() on null

Filename: /home/applerep/public_html/application/views/header_view.php

Line Number: 99

Backtrace:

File: /home/applerep/public_html/application/controllers/Error_404.php
Line: 23
Function: view

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