Canot load soch file -- bcrypt workaround in Ruby On Rails

LoadError in UsersController#create

cannot load such file -- bcrypt

Extracted source (around line #2):

class User < ApplicationRecord

has_secure_password

end

What kind of error is this? Right now, https://www.youtube.com/watch?v=IWBJHO7cUis I'm listening to this lecture and copying it There's a traffic jam here.

It's a membership registration form, but when I press sign up, that error comes up.

I've been trying my brain.

In gemfile, gem "bcrypt", "~>3.1.7" I think there is a problem because the current bcrypt version is 3.1.11.

So I changed the gem 'bcrypt' and '~>3.1.7' to gem 'bcrypt' and '~>3.1.11' in gemfile There's an error just like that.

It's running on c9, so the ctrl+c that kills the server doesn't work It's frustrating