1change your application->config->config.php and set
2
3$config['sess_driver'] = 'database';
4$config['sess_cookie_name'] = 'ci_session';
5$config['sess_expiration'] = 7200;
6$config['sess_save_path'] = 'ci_sessions';
7$config['sess_match_ip'] = FALSE;
8$config['sess_time_to_update'] = 300;
9$config['sess_regenerate_destroy'] = FALSE;
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