Port Opening

Hey so when a person joins my party it auto pops up saying Harrison41 has a restricted Nat and may have trouble connecting to games and i never am able to play CO-OP and i dont no how to fix this can someone please help me?|||

http://forums.ageofempiresonline.com/forums/post/50252.aspx

Search is here for everyone. Hoping this helps.

|||Some routers don't play nice. What is your internet gateway device, and your connection type (cable/DSL)?