Hello again Tom
unluckily the solution didn't work , or maybe it's my mistake , (although it's very easy just a copy) . Is there any other "trick" ?

Thank's again.


(I did this
Try this. Open web/staff/index.php in a text editor and put this line on the top.

ini_set('session.gc_maxlifetime', 24*60*60);

It should be after <?php, so the result should look like this

<?php
ini_set('session.gc_maxlifetime', 24*60*60);

24*60*60 should extend your session to one day ( 24 hours x 60 minutes x 60 seconds ) )

OK then probably some other php files in the same web site are overwriting php session files.
You can have a separete session folder for the script so other scripts won't overwrite it.
To do so, create a folder in your web server. Ideally it should be located below the root directory of the web site because session files contain your login password and you don't want anybody to see it. Also, the session folder should be readable and writeable.
After you create the session folder, put session_save_path ( "--path-to-session-folder--" ) on the top of index.php line. "--path-to-session-folder--" should point to the session folder you just created. The result now should look like

<?php
session_save_path ( "--path-to-session-folder--" );
ini_set('session.gc_maxlifetime', 24*60*60);