这是错误...
C:\Sites\simple_cms>rails s
> => Booting WEBrick
> => Rails 3.2.13 application starting in development on http://X.X.X.X:3000
> => Call with -d to detach
> => Ctrl-C to shutdown server
Exiting
C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/bundler-1.3.5/lib/bundler/rubygems_integ
ration.rb:214:in `block in replace_gem': Please install the mysql2 adapter: `gem
install activerecord-mysql2-adapter` (mysql2 is not part of the bundle. Add it
to Gemfile.) (LoadError)
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/activerecord-3.2.13/lib/act
ive_record/connection_adapters/mysql2_adapter.rb:3:in `<top (required)>'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/activesupport-3.2.13/lib/ac
tive_support/dependencies.rb:251:in `require'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/activesupport-3.2.13/lib/ac
tive_support/dependencies.rb:251:in `block in require'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/activesupport-3.2.13/lib/ac
tive_support/dependencies.rb:236:in `load_dependency'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/activesupport-3.2.13/lib/ac
tive_support/dependencies.rb:251:in `require'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/activerecord-3.2.13/lib/act
ive_record/connection_adapters/abstract/connection_specification.rb:50:in `resol
ve_hash_connection'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/activerecord-3.2.13/lib/act
ive_record/connection_adapters/abstract/connection_specification.rb:41:in `resol
ve_string_connection'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/activerecord-3.2.13/lib/act
ive_record/connection_adapters/abstract/connection_specification.rb:25:in `spec'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/activerecord-3.2.13/lib/act
ive_record/connection_adapters/abstract/connection_specification.rb:130:in `esta
blish_connection'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/activerecord-3.2.13/lib/act
ive_record/railtie.rb:82:in `block (2 levels) in <class:Railtie>'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/activesupport-3.2.13/lib/ac
tive_support/lazy_load_hooks.rb:36:in `instance_eval'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/activesupport-3.2.13/lib/ac
tive_support/lazy_load_hooks.rb:36:in `execute_hook'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/activesupport-3.2.13/lib/ac
tive_support/lazy_load_hooks.rb:43:in `block in run_load_hooks'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/activesupport-3.2.13/lib/ac
tive_support/lazy_load_hooks.rb:42:in `each'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/activesupport-3.2.13/lib/ac
tive_support/lazy_load_hooks.rb:42:in `run_load_hooks'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/activerecord-3.2.13/lib/act
ive_record/base.rb:720:in `<top (required)>'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/activerecord-3.2.13/lib/act
ive_record/railtie.rb:88:in `block in <class:Railtie>'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/railties-3.2.13/lib/rails/i
nitializable.rb:30:in `instance_exec'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/railties-3.2.13/lib/rails/i
nitializable.rb:30:in `run'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/railties-3.2.13/lib/rails/i
nitializable.rb:55:in `block in run_initializers'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/railties-3.2.13/lib/rails/i
nitializable.rb:54:in `each'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/railties-3.2.13/lib/rails/i
nitializable.rb:54:in `run_initializers'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/railties-3.2.13/lib/rails/a
pplication.rb:136:in `initialize!'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/railties-3.2.13/lib/rails/r
ailtie/configurable.rb:30:in `method_missing'
from C:/Sites/simple_cms/config/environment.rb:5:in `<top (required)>'
from C:/Sites/simple_cms/config.ru:3:in `require'
from C:/Sites/simple_cms/config.ru:3:in `block in <main>'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/rack-1.4.5/lib/rack/builder
.rb:51:in `instance_eval'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/rack-1.4.5/lib/rack/builder
.rb:51:in `initialize'
from C:/Sites/simple_cms/config.ru:in `new'
from C:/Sites/simple_cms/config.ru:in `<main>'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/rack-1.4.5/lib/rack/builder
.rb:40:in `eval'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/rack-1.4.5/lib/rack/builder
.rb:40:in `parse_file'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/rack-1.4.5/lib/rack/server.
rb:200:in `app'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/railties-3.2.13/lib/rails/c
ommands/server.rb:46:in `app'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/rack-1.4.5/lib/rack/server.
rb:304:in `wrapped_app'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/rack-1.4.5/lib/rack/server.
rb:254:in `start'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/railties-3.2.13/lib/rails/c
ommands/server.rb:70:in `start'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/railties-3.2.13/lib/rails/c
ommands.rb:55:in `block in <top (required)>'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/railties-3.2.13/lib/rails/c
ommands.rb:50:in `tap'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/railties-3.2.13/lib/rails/c
ommands.rb:50:in `<top (required)>'
from script/rails:6:in `require'
from script/rails:6:in `<main>'
任何帮助将不胜感激，因为我没有高兴地关注了所有其他线程。提前致谢