Quick Answer: Use your Local IP. Read below for details. There is some confusion as to how to connect to your own server, while running it in another instance of the game. Many people are making lots of different threads about the same problem, and none of you seem to care to check the "Guides" section of the forums, and if so, you must have skipped over the guides on how to do this. I'm going to use simple terms so people can understand and relate, so if you net gurus want to nit pick, do it in PMs because I'll gladly chat about this. First off, there are 3 different common IPs you can use: External IP: What people type to connect to you. Whether through Hamachi, or what you get from visiting www.whatismyip.com. Do not use when connecting to your own server. It MAY work, there have been reports of it, but chances are it won't. Local IP: This IP looks like 192.168.xxx.xxx, and it is NOT 192.168.1.1, which would be your router, unless configured otherwise, but if your router is configured like that then chances are you wouldn't be reading this. Use this IP when connecting to your own server. Internal Loopback: This IP is 127.0.0.1, or localhost, and basically means "Me" or "My computer". Unfortunately, this will not work in Terraria for whatever reason. Do not use this to connect to yourself. So give your friends your External IP, and connect with your Local IP yourself. Here's how to find your Local IP in Windows 7: Open up the Network and Sharing Center by right clicking the Network icon on your task bar, next to your clock. Click "Change adapter settings" in the upper left-hand side. Right click the network adapter you use to connect to your router/the internet (this does not mean Hamachi's adapter!), and click "Status". Click the "Details..." button. Find your "IPv4 Address", which should start with 192.168, and connect to yourself with that address every time. NOTE: It's subject to change depending on your network configuration. Double check it if you can't connect anymore Hopefully, this should clear things up. If things STILL don't work, feel free to PM me.