"Failed to connect to server"

I just downloaded the latest patch for this game, but I can't login because as soon as the login screen appears, I get this "Failed to connect to server" crap and it exits the game. Of course it does this just as soon as I buy ZP. If it's a matter of reinstalling the game then this game is just gonna stay uninstalled. My internet takes forever to download anything and I don't feel like waiting an hour or 2 just to fix whatever this problem is (I've got CS:GO, only reason I play this game is because I don't have to go full tryhard every game and a friend plays this with me.) Is there something I can do, or do I just have to wait it out?