我正在浏览RoR教程，我有一个全新的项目。当我运行rails s时，我收到此错误。我确实跑了bundle install。我在Windows 7上使用Rails版本4.2.3。
$ rails s
c:/Ruby22/lib/ruby/gems/2.2.0/gems/actionview-4.2.3/lib/action_view/helpers.rb:4
0:in `<module:Helpers>': uninitialized constant ActionView::Helpers::ActiveModel
Helper (NameError)
from c:/Ruby22/lib/ruby/gems/2.2.0/gems/actionview-4.2.3/lib/action_view
/helpers.rb:4:in `<module:ActionView>'
from c:/Ruby22/lib/ruby/gems/2.2.0/gems/actionview-4.2.3/lib/action_view
/helpers.rb:3:in `<top (required)>'
from c:/Ruby22/lib/ruby/gems/2.2.0/gems/actionview-4.2.3/lib/action_view
/base.rb:5:in `require'
from c:/Ruby22/lib/ruby/gems/2.2.0/gems/actionview-4.2.3/lib/action_view
/base.rb:5:in `<top (required)>'
from c:/Ruby22/lib/ruby/gems/2.2.0/gems/web-console-2.2.1/lib/web_consol
e/template.rb:7:in `<class:Template>'
from c:/Ruby22/lib/ruby/gems/2.2.0/gems/web-console-2.2.1/lib/web_consol
e/template.rb:6:in `<module:WebConsole>'
from c:/Ruby22/lib/ruby/gems/2.2.0/gems/web-console-2.2.1/lib/web_consol
e/template.rb:1:in `<top (required)>'
from c:/Ruby22/lib/ruby/gems/2.2.0/gems/web-console-2.2.1/lib/web_consol
e.rb:12:in `require'
from c:/Ruby22/lib/ruby/gems/2.2.0/gems/web-console-2.2.1/lib/web_consol
e.rb:12:in `<top (required)>'
from c:/Ruby22/lib/ruby/gems/2.2.0/gems/web-console-2.2.1/lib/web-consol
e.rb:1:in `require'
from c:/Ruby22/lib/ruby/gems/2.2.0/gems/web-console-2.2.1/lib/web-consol
e.rb:1:in `<top (required)>'
from c:/Ruby22/lib/ruby/gems/2.2.0/gems/bundler-1.10.5/lib/bundler/runti
me.rb:76:in `require'
from c:/Ruby22/lib/ruby/gems/2.2.0/gems/bundler-1.10.5/lib/bundler/runti
me.rb:76:in `block (2 levels) in require'
from c:/Ruby22/lib/ruby/gems/2.2.0/gems/bundler-1.10.5/lib/bundler/runti
me.rb:72:in `each'
from c:/Ruby22/lib/ruby/gems/2.2.0/gems/bundler-1.10.5/lib/bundler/runti
me.rb:72:in `block in require'
from c:/Ruby22/lib/ruby/gems/2.2.0/gems/bundler-1.10.5/lib/bundler/runti
me.rb:61:in `each'
from c:/Ruby22/lib/ruby/gems/2.2.0/gems/bundler-1.10.5/lib/bundler/runti
me.rb:61:in `require'
from c:/Ruby22/lib/ruby/gems/2.2.0/gems/bundler-1.10.5/lib/bundler.rb:13
4:in `require'
from c:/Users/Morgan Davison/Documents/Code/Rails/Learning/RoR4 Essentia
l Training/simple_cms/config/application.rb:7:in `<top (required)>'
from c:/Ruby22/lib/ruby/gems/2.2.0/gems/railties-4.2.3/lib/rails/command
s/commands_tasks.rb:78:in `require'
from c:/Ruby22/lib/ruby/gems/2.2.0/gems/railties-4.2.3/lib/rails/command
s/commands_tasks.rb:78:in `block in server'
from c:/Ruby22/lib/ruby/gems/2.2.0/gems/railties-4.2.3/lib/rails/command
s/commands_tasks.rb:75:in `tap'
from c:/Ruby22/lib/ruby/gems/2.2.0/gems/railties-4.2.3/lib/rails/command
s/commands_tasks.rb:75:in `server'
from c:/Ruby22/lib/ruby/gems/2.2.0/gems/railties-4.2.3/lib/rails/command
s/commands_tasks.rb:39:in `run_command!'
from c:/Ruby22/lib/ruby/gems/2.2.0/gems/railties-4.2.3/lib/rails/command
s.rb:17:in `<top (required)>'
from bin/rails:4:in `require'
from bin/rails:4:in `<main>'