I have created a minecraft server and I am not using VPN - so I have sorted out port forwarding on my Netgear router (TCP/UDP), dyndns and ensured the firewall is open for the relevant ports. After creating the server on one PC on my network, I cannot access it from another PC on the network. I have tried my external IP address, the internal IP address of the PC running the server and the URL I registered with dyndns. I get "Can't connect to server" (if I use an IP address) and "Can't resolve server name" (if I use the URL). From my second PC, I can ping all these (the external IP address, internal IP address and URL). Here's the fascinating bit: when I have minecraft_server running and try testing the port (25565) from canyouseeme.org or yougetsignal.com, it fails. But... When I run http://www.pcwintech.com/simple-port-tester (an app you download to test ports), then canyouseeme.org or yougetsignal.com say 25565 is open. Which means that the simple-port-tester is listening on 25565 but minecraft_server appears not to be. The server-port in server.properties is set to 25565, and the server dialogue shows it is "Starting Minecrafter server on *:25565". Can anyone help? Solved it!!! I had to set an additional exception in the Windows firewall: javew.exe. I had java.exe in there, but not javaw.exe. Hurray. I hope this helps somebody. EDIT by Moderator: merged posts, please use the edit button instead of double posting.