When I used to test $this->Auth->user('id') locally, it works well
and the file /app/Config/core has this configuration for Session
Configure::write('Session', array(
'defaults' => 'cake'
));
Now it is hosted on my server, I was noticed that I needed to change that file, so it looks like
Configure::write('Session', array(
'defaults' => 'php'
));
But doing this way, I lost $this->Auth->user('id'), the other fields I can find.