Okey ! the problem is done ! thanks for your help Roman, the problem was the mod "extra utilities 2" 
Posts by SupreMeister
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we have 55 mods for this game
if we do that we lose 30h of our life... are you sure for this issue ? -
Hellooo
So its in the title, i cant join an server because of this error. Its not my server, i've try with IP and DynIP but its dosent work.
Idea ? i search for 4 hours now... im done xD