"Unknown Host" Bukkit 1.7.10

I am trying to host a Bukkit Server over a LAN wifi network at a Library that I work at for 16 kids to play on. In the past when I was using an older Windows 7 computer I could host it fine and they could connect without issues.

But recently I tried to run it on a newer Windows 8 computer with more RAM and they all keep getting the "Unknown Host" issue. I made sure to get the IPv4 address from ipconfig and not to copy/paste it in. I've tried multiple times with no luck. I also disabled the firewalls and antivirus just in case they were causing the issue.

Any ideas?

Bukkit.yml

server.properties

The Unknown Host problem normally indicates that the destination computer or host server name cannot be resolved.

I am trying now to give a troubleshooting now with several points. Make sure you check each point! I assume that you have set up the server correctly and you are able to see atleast the server console. A working internet connection is duty on both sides, host and client!

Is the server running?

Make sure the server is running. If there is a error in the start up or plugin installation, it is possible that the server is offline. Also a syntax error in a configuration file could prevent the server from the successful boot. Take a look at the console on the server to find such errors.

Are the properties right?

The server.properties file is the configuration file of the server. It is very important that the field server-ip= is blank. This is one of the biggest mistakes!

Decide if you use the default port or a changed port. If you use the default port make sure the field server-port= contains the port 25565.

Is the owner able to login?

With that I mean you have to be able to join on the server with the localhost IP (client is on the same pc as the host). Always enter the IP or the server name by yourself and do not copy it into the field!

Default Port

This means you have enterd the IP 127.0.0.1 in the direct connect field and you successfully joined on the server.

Modified Port

If you have a port defined you have to enter the localhost IP and the port to be able to join. Means you use the IP and extend the port with a : between the IP and the port. With the port 25570 it looks like this 127.0.0.1:25570.

If you connect like this to the server the signal is actully not leaving your pc. You should not have any problems to join on the server if you have done the previous things right.

Is it possible to connect in the LAN?

The next step is to try to connect over the router. For that you need the LAN IP adress of your pc.

Steps for windows

• Press the windows key + R
• Type cmd and press ok
• Type ipconfig into the commandline
• Search for the IPv4 information of your connection adapter. Make sure you use the right adapter. With that I mean you have to use the LAN adapter if you are connected with a cable to the router or you have to use the WLAN adapter if you are connected wirless to the router.

Memorize this IP adress!

Now type this LAN adress into the direct connect field in minecraft and try to connect with the server. The signal is leaving your pc if you connect like that but leaves not your local network.

At this point there are two solutions that could solve the problem.

You have to be sure that no firewall is blocking the connection. This could be the windows firewall or the firewall of a anti virus (for example Kaspersky). Here is a tutorial for the windows firewall. If you do not use the windows firewall you have to search for your own. There are to many anti virus to provide a tutorial for each.

If this is not working, the router does not let the signal through or throws away the package. Normally the router should not block the signals within the local network. But if that is the case you have to configure your router so, that he let the signal through (This is the only information I can give in this step).

Is it possible to connect through the Internet?

_{If you want that your server is reachable over the world}

For this step you need your public IP adress. You find it on this site! Like in the steps before, type this adress into the direct connect field in minecraft.

If this is not working the problem is that the router does not let the signal through. You have to configure the port forwarding on the router. Make sure the router let the signal through the firewall.

Do not skip any of these steps. Work from the beginning through the last point. If all of these steps working, the host is correctly set up.

Is a client able to connect?

If you want that a client is able to connect to your server, you have to provide the right IP adress. This means you have to use either the public or LAN IP adress. Do not forget the port if you have modified it.

If you want to connect over LAN the client has to be connected with the router and has a working internet connection.

If you want to connect over the internet, the client only needs a working internet connection.

In both cases the firewall has to let the signal through (use the tutorial from above if it is a windows firewall).