A PHP Error was encountered

Severity: Notice

Message: Undefined index: HTTP_REFERER

Filename: controllers/Welcome.php

Line Number: 159

Backtrace:

File: /home/agakiriro/public_html/application/controllers/Welcome.php
Line: 159
Function: _error_handler

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