You are already aware of the Windows firewall issue listed in the FAQ
However, I ran into this issue today--for the first time--when I switched
over from my work to my home network.
As a workaround, I resolved the issue by turning off my wireless network
connection; so it appears the firewall issue is the root of the cause. I
haven't tried the steps in the FAQ. If you're wired, you might try
unplugging from the network to verify cause.