Recently I have developed a web application with codeigniter. I am facing a session related problem there badly.
Problem scenario:
If user
Open the general config file application/config/config.php, search for $config[‘sess_expiration’]
change
$config['sess_expiration'] = 7200;
to
$config['sess_expiration'] = -1;
in $config.php file
change $config['sess_expiration'] = 7200;
to
$config['sess_expiration'] = 0;
Have a look at this, and see if this helps.
https://github.com/EllisLab/CodeIgniter/wiki/PK-Session