"rails server" not working

I am using window 7. I have upgraded rails 2.0.2 to rails 3.0.9 with ruby as 1.8.7. I have changed in evironment.rb as:

RAILS_GEM_VERSION = '3.0.9' unless defined? RAILS_GEM_VERSION

still I am unable to start server.

RubyGems Environment: - RUBYGEMS VERSION: 1.7.2 - RUBY VERSION: 1.8.7 (2011-06-30 patchlevel 352) [i386-mingw32] - INSTALLATION DIRECTORY: C:/InstantRails-2.0-win/ruby/lib/ruby/gems/1.8 - RUBY EXECUTABLE: C:/InstantRails-2.0-win/ruby/bin/ruby.exe - EXECUTABLE DIRECTORY: C:/Ins开发者_JAVA百科tantRails-2.0-win/ruby/bin - RUBYGEMS PLATFORMS: - ruby - x86-mingw32 - GEM PATHS: - C:/InstantRails-2.0-win/ruby/lib/ruby/gems/1.8 - C:/Users/SUKETA/.gem/ruby/1.8 - GEM CONFIGURATION: - :update_sources => true - :verbose => true - :benchmark => false - :backtrace => false - :bulk_threshold => 1000 - :sources => ["http://gems.github.com", "http://rubygems.org/"] - REMOTE SOURCES: - http://gems.github.com - http://rubygems.org/

Any suggestion

Maybe it can help you: http://railscasts.com/episodes/225-upgrading-to-rails-3-part-1

Is part of a complete guide that explain how to do this migration on the right way.

However according to http://weblog.rubyonrails.org/2010/9/4/ruby-on-rails-2-3-9-released (official Rails blog) it is recommended to first migrate to Rails 2.3.9

Migrating from rails 2.0.2 to Rails 3 isn't exactly a simple task. To give you an idea Ryan Bates made 3 screencast about this. You can find out more here; http://railscasts.com/episodes/225-upgrading-to-rails-3-part-1