Start by downloading Minecraft_Server.exe from the official minecraft website.
Place it in an empty folder somewhere on your computer and open it. You'll see the world being created, and when it's done, it'll tell you so. As long as that program is open and running, your server will be available for connection.
Any computer on your LAN will be able to connect to this server now. Simply open minecraft, login and head into multiplayer. Type in the LAN address (found here) of the computer where the server is running, and hit connect. If it doesn't connect on the first try, give it a couple more tries.
- Try changing your firewall settings (XP, Vista/7). The application you're adding is Minecraft_Server.exe, the port is
25565 (or port range
25565), and you want this on both TCP and UDP protocols (you may have to add a rule for each).
- Try port forwarding on your router. If you have access to your router, open your router configuration webpage (um, what?) and find the Port Forwarding section (might be listed under Applications and Gaming). Use the same ports and protocols as above.
- Try setting the server to offline mode. Close the server for a moment. Go into the folder where Minecraft_Server.exe is sitting, and find the
server.properties file (may simply appear as
server). Open this with Notepad and change
online-mode from true to false. Save it, close it, and start the server again.
- Try connecting the computers directly to one another, via ethernet cable. This one will work as a last resort, and is handy for laptops or desktops which are fairly close together. If you're picking up wireless internet or have a second ethernet port in your computer, you won't even have to sacrifice your internet connection.
- Instead of connecting by putting in your LAN address in the server IP box, put in "localhost" (without the quotes) in the server IP box and try to connect.