My mac has problems connecting to Windows

I made a server for a game I play. Its hosted on my Windows PC because its way easier to create. I can connect to it from my PC in a snap, but on my Mac, the game's console tells me this:

[INFO] Disconnecting /192.168.*.***:545**: Protocol error

2013-11-27 12:58:38 [INFO] /192.168.*.***:545** lost connection

2013-11-27 12:59:32

Please help, I've tried Firewall, but its off, I have Norton antivirus, and no programs that could interfere with them. I don't know what to do so please help me. 😀