We have confirmed a problem where all online events in Gran Turismo™ 5 Prologue appear to be closed and players are unable to participate in online events. If this occurs, please go to the game's main menu page and select [Options ] > [Network] > [Clear System Cache].
Once you've done this, please return to My Page, and reselect Online. All events should display properly.
We deeply apologize for any inconvenience this may have caused.