A PHP Error was encountered

Severity: Notice

Message: Undefined index: HTTP_REFERER

Filename: controllers/Main.php

Line Number: 16

Backtrace:

File: /home/central3/public_html/app/controllers/Main.php
Line: 16
Function: _error_handler

File: /home/central3/public_html/index.php
Line: 317
Function: require_once