Set this checked (true) to activate a background thread, which will scan active sessions once a minute for those with inactivity greater than the Session Timeout value.  When a session is found to be timed-out, the session will be stopped (closed).

 

Note that for many application environments, this is not recommended and a specialized logoff script should be employed using one of the available API's.  This is due to the need for a proper logoff procedure to be followed that may entail more than one screen transition to complete.