It's either a firewall issue, or a router issue.
Solution below was taken from
http://vnboards.ign.com/ffxi_tech_support_board/b22547/76532080/p1/
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1. On your router. If you have the option to add "Applications & Gaming" ports. Enter POLBOOT.EXE with port range of 50000 - 65535 protocols are “BOTH” (tcp/udp) and then what ever IP address of your machine is.
2. On your router, again. If you have the option to add "Applications & Gaming" ports. Enter POL.EXE with port range of 50000 - 65535 protocols are “BOTH” (tcp/udp) and then what ever IP address of your machine is.
3. On your firewall you must add the above two applications you set in your router, now on your firewall. You should be able to add polboot.exe and pol.exe to a list of programs your Firewall permits and denies. For these two programs you want to "Permit All" for their "Internet Access".
-This worked for me and it should work for you. This is not set in stone, but has been a proven solution. In addition, if anyone has another useful suggestion, please let us know.
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