Fix for the 500 Internal Server Error after the upgrade to Rails 2.0.1
After trying to find an answer, i found one at http://weblog.rubyonrails.org/2007/12/7/rails-2-0-it-s-done from blog comment #83. Apparently there is a need to seed the session key in the session, with a 30+ character string. In your config/enviornment.rb within the Rails::Initializer.run do |config| / end block add the following: config.action_controller.session = { :session_key => "_myapp_session", :secret => "Any 30+ character string will do here, so choose whatever"} Hope this helps. Enjoy Rails 2.0+