I'm playing via Wi-Fi router.
After joining a server everything runs smooth, but then after 5 minutes (aprox) I kicked with message "lost connection".

This happens only in crysis 2. What is the problem? I can't even get lvl2 !

Have you gone into your router and looked at any type of log to see if by chance you are actually losing a connection (local/ISP network issue) and have you opened up all appropriate ports both in the firewall and in your router. I do not have a list of them since I am not playing online yet but I think if you search for it there is a thread somewhere with proper settings.

I dont know about ports everything was working perfectly (and still working except Crysis).
May dynamic Ip get such problems?