Edit : Gave up and reinstalled the game, works again.
Out of nowhere i got an error, telling me there's an update while there isn't.
(when i press start on the main menu) :
https://gyazo.com/b74fe977c58a4a3153c0951bf8ab6ce8
yesterday and any days before there were no problems at all, this didn't work either :
http://forum.square-enix.com/ffxiv/t...are-no-updates
..any idea?