Okay so, here's a new error that came up when I tried to get on graal.
Well, I've been on graal yesterday and everything was fine.
Today, I tried to launch it, and it was "crashing" (blabla, cannot be opened, program suddendly closed, ...)
I restarted my computer and tried back. Same.
I right-clicked it and tried to launch it as administrator, blabla....
Then:
Owwwww....?