Solution to Undefined method `cache_template_extensions=' in Ruby on Rails

When you upgrade to rails version 2.2.x or later then some times you might get
the below error
Undefined method 'cache_template_extensions='

To fix this problem check your environment.rb and environemts/development.rb, production.rb, test.rb files and comment/remove the below line of code.

config.action_view.cache_template_extensions = false

Restart the server and see output.

Solution to uninitialized constant FileColumn::ClassMethods::Inflector in Ruby on Rails

When you install file column plugin in latest version of rails, you might got this noname or uninitialized error. To fix this error open the plugin/lib/file_colum.rb file goto line number 619 and add ActiveSupport:: before the Inflector. See the final code should be like below at line number 619.

my_options = FileColumn::init_options(options,
ActiveSupport::Inflector.underscore(self.name).to_s,
attr.to_s)

Also at line number 79 find and change as below

url << size="4">Restart the server and see the output.

Rails error: initialize_without_backlog': Address already in use - bind(2)

When try to start the webserver for the application some times this error may happen. This happen when you already run any application in the same port number. Make sure you are not running any other rails application with that same web server in the same system.

If you already start the server one one application, stop it for that application and run for the new application you want.

Good Luck -:)