Why can't I join any rooms?

I got on not long ago and I went to join a HMX game. It loaded for a minute then said "failed to connect to host server", so I tried several other rooms and I got the same thing. The same thing has happened to many people in alpha server, yet I see that some people don't have a single issue about the host connection. I really want to play crossfire, can anybody tell me what's going on, and how to fix it?