Thank for your reply,
I updated the Nvidia driver too.
I downloaded two times the beta client and nothing changed.
I think , i've enough space on my windows partition (8Gb free) and my games/programs partition (130Gb free)
It will be strange if it's the overcloking of the CPU/RAM/GPU cause this problem.
I've the default regional and language setting ...
I'm not very lucky and I hope that the COHOF gold works perfectly.
I saw in COHOF beta forum some firewalls/routers have problem to establish a connection with other players.
Thank you again and have fun