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GitHub User: javierchavez
I don't know if anyone else ran into this problem but I had to put
otherwise it would blow up when redirected back to the homepage after deleting a user account.
you didnt need to roll back you probably were trying to use/login with a user-account that was already in your database. After doing the tutorial, create a new user so the auth_token column is populated and it will fix your error. @fritzsche created a rake tasks that will fix all your current users in your database incase you dont want to do a rake db:migrate:reset.
in short you cannot login with a old user after doing this.