You're using tracert, right? It should work fine in Vista. In any case, if you can't connect to those 2 servers, but can connect to others, then it's an issue on the network. You have a couple of options. Try using a different port when connecting to them (instead of 6667, use 6669 for example). Or, you can try connecting to the servers using their IP addresses. There are a variety of lookup sites that can give you the IP of those servers (try google). Or, you can try a different server on that network.

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