sess_expire_on_close

sess_expire_on_close is an old config item that is no longer in use.
See note on this link http://www.codeigniter.com/user_guide/li...references

When a user checks a 'remember me' box, set a cookie with some reference details. When a person visits the login page (or wherever) you can check for the presence of the cookie, read the details and do whatever you need to do (such as login etc).

Let the CI sessions run as normal.

Best wishes,

Paul.