My friend had this same problem, he has no wifi near or in his house so he needed to use a USB-stick that contained the wifi. However, when he installed the game it gave him that message. I came over to try to help him and figured out that although he had wifi, it wasn't strong enough or sending well enough signal. Unfortunately he wasn't able to get FH because his internet connection was constantly cutting out.
If you have frequent bad connection to your wifi or your USB only provides a certain amount of wifi for acertain amount of time (like my friend's did) then FH may be too much of a server to run on your computer.
I do apologize for the unfortunate news, but if none of this is the case, then I'm not sure what it could be~
If you'd like to play around with making characters (though not being able to save them or play in-game with them) you could click Preset Maker on the login screen. This doesn't require internet connection or for you to log in.