Good afternoon and thank you for posting on the Final Fantasy XIV Technical Support Forums.

Are these crashes consistent? If you were to start any dungeon, it will crash with the same error message, correct? Do you get this message at any other point in the game?

I would suggest trying a clean boot. Simply open the task manager and select the 'Start up' Tab. Disable everything here and restart the PC.

I would also suggest making an exception for the game for any anti-virus/firewall you may be using.

We hope we can be of assistance in helping you enjoy the exciting world of Final Fantasy XIV!