Final Fantasy XI Errors

I have been getting disconnected after many tries to configure my router for the game. Of course I can never get through to their tech support, as it seems to be busy for three hours straight.

The error I have been getting is FFXI-4002 and after some research I found that other people had the same error before they configured their router correctly to handle the game.

I've tried many times to get the right settings for my router (Linksys BEFSX41) and nothing seems to work, not even DMZ. The game simply freezes a few minutes into playing it and the 4002 error appears, closing it off.

Any ideas out there?

Well, I found the problem. Turns out the entire router's firewall was conflicting, not just portions.

Help! I am having the exact problems now! I am also using the same router. What did you do?