Can't connect!!!

[giovany]

Hello, please help:
My friend can't join to eurobattle when she cames to my house. She has a computer and I have another, but if I join, she can't join! Is it because we have the same ip? When she clicks on the Battle.net button, appears the error that appears when the server is off..... But if I'm not connected, she can join... I don't know what to do!!! If I play, she doesn't!
Thank you

[Mitsuki]

The problem would be in how you connect your computers to LAN and the settings of router.

[giovany]

But my ports 6112-6119 are unlocked and I can host.... We both use wireless and sometimes I use cable and she uses wireless....Help
Thank's