Codesigniter -Sitzung zerstören automatisch nach dem Umleiten
//if you are working in CI 3.x and
//just upgraded your server php version to php 7.x
//Go to system/libraries/Session/session.php search for and replace
ini_set('session.name', $params['cookie_name']);
//by
ini_set('session.id', $params['cookie_name']);
hansal