Ruby on rails Rails生成错误-'；方法u缺失'；：未定义的方法'；活动记录'；

我在OS X Yosemite 10.10.4上运行Rails 4.2.3。我目前有两个应用程序运行良好，但是在创建新应用程序并尝试使用“rails generate”时，我遇到以下错误消息：

/Library/Ruby/Gems/2.0.0/gems/railties-4.2.3/lib/rails/railtie/configuration.rb:95:in `method_missing': undefined method `active_record' for #<Rails::Application::Configuration:0x007f9d11ae5ed8> (NoMethodError)
from /Users/tompickard/Documents/app/config/application.rb:24:in `<class:Application>'
from /Users/tompickard/Documents/app/config/application.rb:10:in `<module:App>'
from /Users/tompickard/Documents/app/config/application.rb:9:in `<top (required)>'
from /Library/Ruby/Gems/2.0.0/gems/spring-1.3.6/lib/spring/application.rb:82:in `require'
from /Library/Ruby/Gems/2.0.0/gems/spring-1.3.6/lib/spring/application.rb:82:in `preload'
from /Library/Ruby/Gems/2.0.0/gems/spring-1.3.6/lib/spring/application.rb:143:in `serve'
from /Library/Ruby/Gems/2.0.0/gems/spring-1.3.6/lib/spring/application.rb:131:in `block in run'
from /Library/Ruby/Gems/2.0.0/gems/spring-1.3.6/lib/spring/application.rb:125:in `loop'
from /Library/Ruby/Gems/2.0.0/gems/spring-1.3.6/lib/spring/application.rb:125:in `run'
from /Library/Ruby/Gems/2.0.0/gems/spring-1.3.6/lib/spring/application/boot.rb:18:in `<top (required)>'
from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/rubygems/core_ext/kernel_require.rb:55:in `require'
from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/rubygems/core_ext/kernel_require.rb:55:in `require'
from -e:1:in `<main>'

/Library/Ruby/Gems/2.0.0/Gems/railties-4.2.3/lib/rails/railtie/configuration.rb:95:in'method_missing'：未定义的方法'active_record'（NoMethodError）
from/Users/tompickard/Documents/app/config/application.rb:24:in`'
from/Users/tompickard/Documents/app/config/application.rb:10:in`'
from/Users/tompickard/Documents/app/config/application.rb:9:in`'
from/Library/Ruby/Gems/2.0.0/Gems/spring-1.3.6/lib/spring/application.rb:82:in'require'
from/Library/Ruby/Gems/2.0.0/Gems/spring-1.3.6/lib/spring/application.rb:82:in'preload'
from/Library/Ruby/Gems/2.0.0/Gems/spring-1.3.6/lib/spring/application.rb:143:in'serve'
from/Library/Ruby/Gems/2.0.0/Gems/spring-1.3.6/lib/spring/application.rb:131:in'block in run'
from/Library/Ruby/Gems/2.0.0/Gems/spring-1.3.6/lib/spring/application.rb:125:in'loop'
from/Library/Ruby/Gems/2.0.0/Gems/spring-1.3.6/lib/spring/application.rb:125:in'run'
from/Library/Ruby/Gems/2.0.0/Gems/spring-1.3.6/lib/spring/application/boot.rb:18:in`'
from/System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/Ruby/2.0.0/rubygems/core\u ext/kernel\u require.rb:55:in'require'
from/System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/Ruby/2.0.0/rubygems/core\u ext/kernel\u require.rb:55:in'require'
from-e:1:in`'

我尝试过各种各样的解决办法，但都无济于事。 如果你需要更多的信息，请告诉我

---

谢谢

您的活动记录方法定义了吗？它将在哪里定义？运行

gem update--system

更新返回到rails 4.1.0后，我仍然收到相同的错误，现在已经修复了它