My daughter and I were playing a creative map on my Window 10, her on the Kindle Fire. Windows crashed hard, gave me the blue screen and told me it was going to have to restart. That of course kicked her off. The computer restarted, I reloaded and she tried to join but when the map loaded it kicked her out of minecraft and back to the Kindle home screen. It does it every time. She can join my other maps though, just not the one we were in together when my computer crashed even though I can get back into it.