"Server is not responding"

I’ve done google research, everyone says to do something, I forget what it was but:I did it, and my friends still can’t connect! It’s not lan, I even tried in the console: lan_0 and heartbeat a couple times. But no one can connect, what do I do?

:pwn:

It’s not lan_0, it’s sv_lan 0
And you need open ports.

Find your router, find any source engine game, and then follow the guide.