Modules tab does not display any modules

[patrmich]

Hi,
I am facing the following problem :
My shop was built under Prestashop v1.3.1.1
As I did not managed to upgrade to v1.4, I re-installed v1.3.1.1
But after such re-installation, the Modules tab does not display any modules !
The problem is the same for the Payment tab
Other tabs work correctly.

Has anyone any idea of the origin of such problem ?

Thank you in advance for any reply.

Patrick