Minecraft Java/LAN problem?

Miscellaneous Topics
#1

I have 3 computers on a LAN at home. All 3 have minecraft installed as the family love to play together. Recently I upgraded one PC from an AMD dual-core to an Intel i7, and now I’m in network hell, in that 2 computers can join the same game but a 3rd PC won’t.

All three are running JDK7u71, all 3 are getting the IP’s from a modem router running DHCP. No mac address filters etc

All three can login into minecraft & play single-player Ok.

All three have windows firewall entries for both the JDK and for minecraft (JDK & minecraft installs did these on their own it seems).

All three are running the same version of Minecraft/Forge and misc mods.

2 PC’s are running Windows 7 Ultimate.
1 PC is running Windows 8.1. <— This is the one that cannot connect to a LAN game with the others.

Any ideas as to what else I should try?

#2

What message does the Windows 8.1 machine give you when you fail to connect to the server over LAN?

#3

opiop65,
It’s a generic error that we get in minecraft (similar to cannot connect to server). I think it maybe a ConnectionException of sorts, but you watch it as it tries and then time-outs. I’m not sure if there is a log file that I can look at it. There is one in the launcher app but I don’t know how to get back to the launcher once you’ve started the game?

I’ll come back with the exact message after work today.

#4

Use PING to determine IP-connectivity among peers.
Use a dummy HTTP server to determine TCP-connectivity on port 80.
Turn off the firewall(s) temporarily to see whether that affects anythings.

#5

I can ping the PC the opened it game to LAN.
I can also start multiplayer, add a server like ‘meepcraft.com’ and play on that successfully.

I just can’t seem to join my kids LAN game when they play together. :frowning:

I’m not quite sure what this new HomeGroup versus WorkGroup settings are in win 8.1. I’m not even sure if it’s that important as my modem/router is the one dishing out the addresses to devices…