I installed ruby-1.9.3-p0 on my Ubuntu 11.10 wubi and then rubygems to get Rails set up. This is my code: sudo ruby setup.rb I got this error: "/usr/local/lib/ruby/1.9.1/yaml.rb:56:in'<top(required)>': It seems your ruby installation is missing psych (for YAML output). To eliminate this warning, please install libyaml and reinstall your ruby." I installed libyaml and reinstalled Ruby but still it