I recently changed my X-BOX live signin email, adding the new one, making it primary, and demoting the old primary to secondary.  I seem to be able to sign in with either one, but minecraft crashes at the "signing in" after hitting the "Let's Play".

I swapped the old primary back to primary and made the new primary a secondary, and now I can get into the game.  Not sure why it won't accept a new primary email address?