Game won't connect on network

I have the game Tiberian Sun and the Firestorm upgrade. I have it installed on our wireless network. It uses the IPX protocol. The multiplayer was working fine until I went online and was told about an automatic update to play on the internet. I upgraded the first machine and then wasn't able to play on the wireless network again. The upgraded machine can see the players on our network but the other one can't see the other players. I tried upgrading the second machine but I still have the same problem. I tried uninstalling on both machines and reinstalling so that it's the same original version on both but no luck. I turned off the firewall and still no luck. It seems as if the information is flowing in one direction; from the second computer to the first. Every other application works just fine across the network. I'm running Windows 98. I tried enabling NetBIOS over IPX/SPX on both machines with no luck (it wasn't enabled before). I changed the Frame Type from Auto to Ethernet 802.3 and then 802.2 with no luck. I also changed the Network Address value from 0 to 10 with no luck. Any suggestions?