Q: bcrypt_ext. so (LoadError) I get the following Error when i try to start the rails server. 
Any ideas? 
Im using a 
32bit Windows 7 machine with Ruby on Rails 4 and ruby 2.0.0p247 . I included the gem "bcrypt-ruby", "~> 3.1.1" in my gemfile.
Heres my stack trace.
rails s
ansi: 'gem install win32console' to use color on Windows
=> Booting WEBrick
=> Rails 4.0.0 application starting in development on http://0.0.0.0:3000
=> Run `rails server -h` for more startup options
=> Ctrl-C to shutdown server
Exiting
C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_support/depen
dencies.rb:228:in `require': 126: The specified module could not be found.   - C
:/Ruby200/lib/ruby/gems/2.0.0/gems/bcrypt-ruby-3.1.1-x86-mingw32/lib/bcrypt_ext.
so (LoadError)
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/dependencies.rb:228:in `block in require'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/dependencies.rb:211:in `block in load_dependency'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/dependencies.rb:615:in `new_constants_in'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/dependencies.rb:211:in `load_dependency'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/dependencies.rb:228:in `require'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/bcrypt-ruby-3.1.1-x86-mingw32/l
ib/bcrypt.rb:12:in `<top (required)>'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/dependencies.rb:228:in `require'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/dependencies.rb:228:in `block in require'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/dependencies.rb:211:in `block in load_dependency'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/dependencies.rb:615:in `new_constants_in'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/dependencies.rb:211:in `load_dependency'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/dependencies.rb:228:in `require'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/devise-3.0.0.rc/lib/devise/mode
ls/database_authenticatable.rb:2:in `<top (required)>'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/devise-3.0.0.rc/lib/devise/mode
ls.rb:97:in `const_get'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/devise-3.0.0.rc/lib/devise/mode
ls.rb:97:in `block (2 levels) in devise'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/devise-3.0.0.rc/lib/devise/mode
ls.rb:92:in `each'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/devise-3.0.0.rc/lib/devise/mode
ls.rb:92:in `block in devise'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/devise-3.0.0.rc/lib/devise/mode
ls.rb:123:in `devise_modules_hook!'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/devise-3.0.0.rc/lib/devise/mode
ls.rb:90:in `devise'
        from C:/Sites/Rubicon/prephub/app/models/authentication/user.rb:5:in `<c
lass:User>'
        from C:/Sites/Rubicon/prephub/app/models/authentication/user.rb:1:in `<t
op (required)>'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/dependencies.rb:423:in `load'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/dependencies.rb:423:in `block in load_file'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/dependencies.rb:615:in `new_constants_in'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/dependencies.rb:422:in `load_file'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/dependencies.rb:323:in `require_or_load'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/dependencies.rb:462:in `load_missing_constant'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/dependencies.rb:183:in `const_missing'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/inflector/methods.rb:228:in `const_get'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/inflector/methods.rb:228:in `block in constantize'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/inflector/methods.rb:224:in `each'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/inflector/methods.rb:224:in `inject'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/inflector/methods.rb:224:in `constantize'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/dependencies.rb:534:in `get'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/dependencies.rb:565:in `constantize'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/devise-3.0.0.rc/lib/devise.rb:2
74:in `get'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/devise-3.0.0.rc/lib/devise/mapp
ing.rb:77:in `to'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/devise-3.0.0.rc/lib/devise/mapp
ing.rb:72:in `modules'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/devise-3.0.0.rc/lib/devise/mapp
ing.rb:89:in `routes'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/devise-3.0.0.rc/lib/devise/mapp
ing.rb:156:in `default_used_route'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/devise-3.0.0.rc/lib/devise/mapp
ing.rb:66:in `initialize'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/devise-3.0.0.rc/lib/devise.rb:3
08:in `new'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/devise-3.0.0.rc/lib/devise.rb:3
08:in `add_mapping'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/devise-3.0.0.rc/lib/devise/rail
s/routes.rb:208:in `block in devise_for'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/devise-3.0.0.rc/lib/devise/rail
s/routes.rb:207:in `each'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/devise-3.0.0.rc/lib/devise/rail
s/routes.rb:207:in `devise_for'
        from C:/Sites/Rubicon/prephub/config/routes.rb:2:in `block in <top (requ
ired)>'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/actionpack-4.0.0/lib/action_dis
patch/routing/route_set.rb:316:in `instance_exec'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/actionpack-4.0.0/lib/action_dis
patch/routing/route_set.rb:316:in `eval_block'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/actionpack-4.0.0/lib/action_dis
patch/routing/route_set.rb:294:in `draw'
        from C:/Sites/Rubicon/prephub/config/routes.rb:1:in `<top (required)>'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/dependencies.rb:222:in `load'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/dependencies.rb:222:in `block in load'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/dependencies.rb:213:in `load_dependency'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/dependencies.rb:222:in `load'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/railties-4.0.0/lib/rails/applic
ation/routes_reloader.rb:40:in `block in load_paths'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/railties-4.0.0/lib/rails/applic
ation/routes_reloader.rb:40:in `each'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/railties-4.0.0/lib/rails/applic
ation/routes_reloader.rb:40:in `load_paths'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/railties-4.0.0/lib/rails/applic
ation/routes_reloader.rb:16:in `reload!'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/railties-4.0.0/lib/rails/applic
ation/routes_reloader.rb:26:in `block in updater'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/file_update_checker.rb:75:in `call'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/file_update_checker.rb:75:in `execute'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/railties-4.0.0/lib/rails/applic
ation/routes_reloader.rb:27:in `updater'
        from C:131071:in `execute_if_updated'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/railties-4.0.0/lib/rails/applic
ation/finisher.rb:69:in `block in <module:Finisher>'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/railties-4.0.0/lib/rails/initia
lizable.rb:30:in `instance_exec'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/railties-4.0.0/lib/rails/initia
lizable.rb:30:in `run'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/railties-4.0.0/lib/rails/initia
lizable.rb:55:in `block in run_initializers'
        from C:/Ruby200/lib/ruby/2.0.0/tsort.rb:150:in `block in tsort_each'
        from C:/Ruby200/lib/ruby/2.0.0/tsort.rb:183:in `block (2 levels) in each
_strongly_connected_component'
        from C:/Ruby200/lib/ruby/2.0.0/tsort.rb:219:in `each_strongly_connected_
component_from'
        from C:/Ruby200/lib/ruby/2.0.0/tsort.rb:182:in `block in each_strongly_c
onnected_component'
        from C:/Ruby200/lib/ruby/2.0.0/tsort.rb:180:in `each'
        from C:/Ruby200/lib/ruby/2.0.0/tsort.rb:180:in `each_strongly_connected_
component'
        from C:/Ruby200/lib/ruby/2.0.0/tsort.rb:148:in `tsort_each'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/railties-4.0.0/lib/rails/initia
lizable.rb:54:in `run_initializers'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/railties-4.0.0/lib/rails/applic
ation.rb:215:in `initialize!'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/railties-4.0.0/lib/rails/railti
e/configurable.rb:30:in `method_missing'
        from C:/Sites/Rubicon/prephub/config/environment.rb:5:in `<top (required
)>'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/dependencies.rb:228:in `require'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/dependencies.rb:228:in `block in require'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/dependencies.rb:213:in `load_dependency'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/activesupport-4.0.0/lib/active_
support/dependencies.rb:228:in `require'
        from C:/Sites/Rubicon/prephub/config.ru:3:in `block in <main>'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/rack-1.5.2/lib/rack/builder.rb:
55:in `instance_eval'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/rack-1.5.2/lib/rack/builder.rb:
55:in `initialize'
        from C:/Sites/Rubicon/prephub/config.ru:in `new'
        from C:/Sites/Rubicon/prephub/config.ru:in `<main>'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/rack-1.5.2/lib/rack/builder.rb:
49:in `eval'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/rack-1.5.2/lib/rack/builder.rb:
49:in `new_from_string'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/rack-1.5.2/lib/rack/builder.rb:
40:in `parse_file'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/rack-1.5.2/lib/rack/server.rb:2
77:in `build_app_and_options_from_config'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/rack-1.5.2/lib/rack/server.rb:1
99:in `app'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/railties-4.0.0/lib/rails/comman
ds/server.rb:48:in `app'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/rack-1.5.2/lib/rack/server.rb:3
14:in `wrapped_app'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/railties-4.0.0/lib/rails/comman
ds/server.rb:75:in `start'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/railties-4.0.0/lib/rails/comman
ds.rb:78:in `block in <top (required)>'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/railties-4.0.0/lib/rails/comman
ds.rb:73:in `tap'
        from C:/Ruby200/lib/ruby/gems/2.0.0/gems/railties-4.0.0/lib/rails/comman
ds.rb:73:in `<top (required)>'
        from bin/rails:4:in `require'
        from bin/rails:4:in `<main>'


A: It seems Rails has_secure_password needs you to use 3.0.0 for some reason. Try
gem 'bcrypt-ruby', '~> 3.0.0'

A: I think following steps may help:


*

*Make sure you have got the Devkit.

You may find something useful about it here: 
https://github.com/oneclick/rubyinstaller/wiki/development-kit


*gem install bcrypt --platform=ruby
Then you can test it in irb by type require 'bcrypt'. If the outcome is true rather than some error message than it is successfully installed.
