With file encryption, just like any other type of computer security, it's never a matter of if someone can break through it, just a matter of how much time and effort it will take to do it. Hopefully it will be difficult enough that A) people will give up because getting through is just not worth the effort or B) it is so difficult and time consuming that it will "keep the Barbarians at the gate" long enough for you to install a newer and different security system in place, thereby putting the hacker back to square one. But it is a game and if somebody really want to get in, they will.