NameError in Devise/registrationsController#create

Im trying to use the gem Devise for a admin authentication. Ive used i开发者_Python百科t before when I only wanted a user login but now I would like to have just a admin login. I followed the railscast for it and instead of naming the model User I gave it the name Admin. Everything worked fine until I tried to login then I got this error message:

uninitialized constant Devise::Encryptors::Bcrypt

I cant seem to find the problem. I have compared the code in the project with the other one I did and there is no difference. Is the problem due to the fact that I´m using Admin the wrong way?! Should I not use it as you would with a user?! Thankful for all help.

Regards

That encryption method appears to have been removed from Devise.

See: https://github.com/plataformatec/devise/issues/issue/527