Hm. The numbers aren't in the FAQ.

I do know that the receiver gets its song data via HTTP on port 12078. But in your case, it's not getting even that far, because it can't even get its main initial software download.

See, when you power on the receiver, it downloads its player software via the NFS protocol. I'm not sure which ports you have to open for that. But if you could find that information, that might be enough: Open the ports for NFS, and open 12078, and see if that works.

Edit: Looks like 2049 is NFS. If the receiver works without the firewall, try opening 2049 and 12078. I don't recall if there is a way in Windows Firewall to only open the ports to specific local addresses or not.