i enabled error reporting by adding the following code at line 1:
<?php error_reporting(E_ALL); ini_set('display_errors','on'); ?>
This shows the following error
Warning: session_start(): open(/var/php_sessions/sess_d97e9feb4f90e0f6ec6b740fcda15f06, O_RDWR) failed: No such file or directory (2)
this is caused by a setting in the php.ini file, you will need to contact the host to have them correct the session.save_path