Terraria Hosting Bug

This bug is known and is being worked on for the next update, or so we hope.

Currently Terraria only listens to the first Network interface listed in Network Connections. If you have multiple network connections or Home/Public network profiles, the port forwarding will not update across them all. Removing or closing extra network connections may solve this issue.
To bypass this for now, Hamachi is a viable option to launch and connect to servers without having to port forward. We will be working towards a simpler automatic solution in the near future.

~http://www.terraria.org/issues.html