Launcher forget my account

When I try to launch the launcher, I am automatically logged out. This is done every time by the launcher even though I select the box that says "remember my log in". Then when I launch the game, and join a server, it says invalid log in please close the game and try again. I do that and i am logged out again. For some reason the launcher is unable to remember my account after I launch the game which makes the game literally unplayable.