A PHP Error was encountered

Severity: Notice

Message: Undefined index: HTTP_REFERER

Filename: controllers/langSwitch.php

Line Number: 24

Backtrace:

File: C:\inetpub\vhosts\a-track.de\login.a-track.de\trackApp\controllers\langSwitch.php
Line: 24
Function: _error_handler

File: C:\inetpub\vhosts\a-track.de\login.a-track.de\index.php
Line: 317
Function: require_once