My launcher wont work! Since I got the new launcher my game crashes before it even opens. this happens on all of my computer devices! Now I have to live with my iPad Minecraft that crashes after the first ten seconds of playing.

Ever since I downloaded 1.12 my launcher crashes before the game even launches. It leaves a pop-up saying that an unexpected error occurred every time! Please fix, it happens on all of my computers, even my Grandmas