Error when execute rails generate scaffold User name:string email:string - ruby-on-rails

Question

I am completely newby in Ruby and I am following the tutorial made by Michael Hartl.
In Chapter 2, Page 49, the book indicates:
rails generate scaffold User name:string email:string
After execute this, the application shows:
C:\demo_app>rails generate scaffold User name:string email:string
C:/demo_app/config/environments/development.rb:1:in `<top (required)>': undefine
d method `configure' for #<DemoApp::Application:0x35d3d98> (NoMethodError)
from C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/activesupport-
3.2.3/lib/active_support/dependencies.rb:251:in `require'
from C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/activesupport-
3.2.3/lib/active_support/dependencies.rb:251:in `block in require'
from C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/activesupport-
3.2.3/lib/active_support/dependencies.rb:236:in `load_dependency'
from C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/activesupport-
3.2.3/lib/active_support/dependencies.rb:251:in `require'
from C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/railties-3.2.3
/lib/rails/engine.rb:571:in `block in <class:Engine>'
from C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/railties-3.2.3
/lib/rails/initializable.rb:30:in `instance_exec'
from C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/railties-3.2.3
/lib/rails/initializable.rb:30:in `run'
from C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/railties-3.2.3
/lib/rails/initializable.rb:55:in `block in run_initializers'
from C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/railties-3.2.3
/lib/rails/initializable.rb:54:in `each'
from C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/railties-3.2.3
/lib/rails/initializable.rb:54:in `run_initializers'
from C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/railties-3.2.3
/lib/rails/application.rb:136:in `initialize!'
from C:/demo_app/config/environment.rb:5:in `<top (required)>'
from C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/railties-3.2.3
/lib/rails/application.rb:103:in `require'
from C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/railties-3.2.3
/lib/rails/application.rb:103:in `require_environment!'
from C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/railties-3.2.3
/lib/rails/commands.rb:25:in `<top (required)>'
from bin/rails:4:in `require'
from bin/rails:4:in `<main>'
I have already use bundle install, bundle update, installed new (and old) version of gems...
Could someone oriented me about what is wrong?
Or a way to avoid this mistake in order to follow with the next steps.
Thanks,

Answer 1

Try this:
bundle exec rails generate scaffold User name:string email:string

Answer 2

I solved the problem.
The steps were:
Correct the file development.rb including in the first line DemoApp::Application.configure do
Later I found another problem when I tried to execute rails generate scaffold User name:string email:string.
The description of the problem was:
C:\demo_app>rails generate scaffold User name:string email:string
invoke active_record
C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/activerecord-3.2.3/lib/acti
ve_record/dynamic_matchers.rb:50:in method_missing': undefined methodmigratio
n_error=' for ActiveRecord::Base:Class (NoMethodError)
Finally, I deleting the following line in config/environments/development.rb:
config.active_record.migration_error = :page_load
I used a mix between the next answers:
rake aborted! undefined method `migration_error=' for ActiveRecord::Base:Class
Error launching Rails server: undefined method 'configure'