bundle install: Failed to build gem native extension

i have git clone git://github.com/jalagrange/excel_test_app.git I got the below error while the bundle install, This does not happen with other my applications. following error ``` Installing mysql2 (0.3.6) with native extensions Gem::Installer::ExtensionBuildError: ERROR: Failed to build gem native extension. C:/RailsInstaller/Ruby1.9.3/bin/ruby.exe extconf.rb checking for rb_thread_blocking_region()... yes checking for main() in -llibmysql... no *** extconf.rb failed *** Could not create Makefile due to some reason, probably lack of necessary libraries and/or headers. Check the mkmf.log file for more details. You may need configuration options. ``` gemfile ``` source 'http://rubygems.org' gem 'rails', '3.1.0' # Bundle edge Rails instead: # gem 'rails', :git => 'git://github.com/rails/rails.git' gem 'sqlite3' gem "spreadsheet" gem "carrierwave" gem "mini_magick" gem 'flash_cookie_session' gem "pry" gem "haml" gem 'fog' # To use Delayed_job gem 'daemons' gem 'delayed_job_active_record' # Gems used only for assets and not required # in production environments by default. group :assets do gem 'sass-rails', " ~> 3.1.0" gem 'coffee-rails', "~> 3.1.0" gem 'uglifier' end gem 'jquery-rails' # Use unicorn as the web server # gem 'unicorn' # Deploy with Capistrano # gem 'capistrano' # To use debugger # gem 'ruby-debug19', :require => 'ruby-debug' group :test do # Pretty printed test output gem 'turn', :require => false end group :development, :test do gem "mysql2", "0.3.6" gem "letter_opener" gem "pry" end ``` this question and answer not working for my problem.. gem install: Failed to build gem native extension (can't find header files) problem solved, i have run bundle update.. thx all..