CI2 to CI3 : error Call to a member function helper()

Hello, I have performed a migration in codeigniter version 2 to version 3,
I have a error in the logs :

Code:

Call to a member function helper() on a non-object in Session.php on line 76

I have consulted the link http://forum.codeigniter.com/thread-61901.html

But this has not helped me.


I need your help please