Unable to reach game server (Multiplayer hosting issue)

[nakedjulia]

I recently updated from an older build (don't remember which one...) and am now unable to host multiplayer servers, whereas with the older build I wasn't having any issues. When I try to host, the command prompt in the background says "Unable to advertise: unable to reach game server, make sure your ports are open." I have opened my ports already and checked multiple times to see if they were open.  I also tried disabling my antivirus (not sure if this would effect anything, but hey, may as well.) 

I'm not sure if this is an issue on my end or a problem with the newer build. 

I can provide the longer message if necessary.