No devices showing in Network Security Map

Hi,

I'm trying to allow computers on my home network to access my main computer so that it can be used as a Minecraft server.  I have set this up before with no problem but now it seems that Norton is preventing any computers from connecting to the server.  I cannot ping the other computers and I cannot see them in Network Security Map.  I have made my home network fully trusted, but still nothing.  I have been able to see the other computers previously.  I'm wondering if Symantec is doing something that is protecting me from myself.  I added both computers to my home group, and I added them as trusted devices, but still nothing.

Any ideas what could be doing this?  I'm running Windows 8.1.  I've checked the Microsoft security settings and verified that everything is being controlled by Norton Internet Security.

Thanks,

MIke