Can't connect to only one server with only one PC on the same connection

[Mr.Phi]

Hello,

At first I am French, I'd like apologize for my bad grammar.

I can't connect to one server with only one PC from the same connection. This PC can connect to any other server.
I already used this server with this PC (even a lot).

Config :
Windows 7

What I tried :
I'm not banned (we checked the banlist and even the file on ssh). I deleted all my TS3 configurations, I checked the host file, changed my local IP, reset my router, I have no antivirus (or virus neither), I have no firewall, I tried the same IP with an other port.

[Mr.Phi]

Resolved I don't know how.