Hi guys, this happened to me tonight. I searched and it appears if you force a launcher update it all works our (Confirmed its worked for me!!)

Go to: my documents\my games\FINAL FANTASY XIV - A realm Reborn\

Edit the file FFXIV_BOOT.cfg

Edit the line: BootVersionCheckMode from 0 to 1

Then relaunch your game and it will update the game.