I have the same problem for the last 5 days, could play without problems before this. Made a support ticket but getting no responses on it I spent real cash on this game and been unable to play since, needless to say i won't be spending any more this is a joke.
4th time reinstalling the game and this time I got got disconnected without a prompt and was given a screen that states G30 followed by G99 upon booting up the game again. There is a direct connection with all the times I have been booted and my client refuses to cooperate: they all happen around 1:00am EST. All the times I have been disconnected it has been around 1:00am, because I was in the middle of doing something I thought it doing something in the game, but all of the actions I have taken leading up to the crash have always been around 1:00am in the morning followed by a loading screen on boot up that boots me to a webpage stating G99 upon reaching 100%. I hope this helps in finding the bug.
I found solution for those who have installed peerblock exit it while playing game it will work, if not - try to do as Sean said
my Game crashes when it reaches 66% i re installed it still didn't work everything is updated please help
Would you look at this. 2016 and it's doing it for me. I have allowed PS2 through my firewall and I have JUST reinstalled. To no avail.