Problem generate migration

Hello, I have Ruby installed in my Windows 7, but when I try to generate a new migration, this error appears:

C:\rails\organily>rails g migration Task       invoke active_record C:/Ruby193/lib/ruby/1.9.1/psych.rb:203:in `parse': (<unknown>): mapping values a re not allowed in this context at line 8 column 13 (Psych::SyntaxError)         from C:/Ruby193/lib/ruby/1.9.1/psych.rb:203:in `parse_stream'         from C:/Ruby193/lib/ruby/1.9.1/psych.rb:151:in `parse'         from C:/Ruby193/lib/ruby/1.9.1/psych.rb:127:in `load'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/railties-3.2.3/lib/rails/applic ation/configuration.rb:115:in `database_configuration'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/activerecord-3.2.3/lib/active_r ecord/railtie.rb:75:in `block (2 levels) in <class:Railtie>'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/activesupport-3.2.3/lib/active_ support/lazy_load_hooks.rb:36:in `instance_eval'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/activesupport-3.2.3/lib/active_ support/lazy_load_hooks.rb:36:in `execute_hook'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/activesupport-3.2.3/lib/active_ support/lazy_load_hooks.rb:43:in `block in run_load_hooks'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/activesupport-3.2.3/lib/active_ support/lazy_load_hooks.rb:42:in `each'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/activesupport-3.2.3/lib/active_ support/lazy_load_hooks.rb:42:in `run_load_hooks'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/activerecord-3.2.3/lib/active_r ecord/base.rb:721:in `<top (required)>'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/activerecord-3.2.3/lib/active_r ecord/migration.rb:507:in `next_migration_number'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/activerecord-3.2.3/lib/active_r ecord/migration.rb:334:in `method_missing'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/activerecord-3.2.3/lib/rails/ge nerators/active_record.rb:21:in `next_migration_number'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/railties-3.2.3/lib/rails/genera tors/migration.rb:49:in `migration_template'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/activerecord-3.2.3/lib/rails/ge nerators/active_record/migration/migration_generator.rb:10:in `create_migration_ file'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/thor-0.14.6/lib/thor/task.rb:22 :in `run'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/thor-0.14.6/lib/thor/invocation .rb:118:in `invoke_task'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/thor-0.14.6/lib/thor/invocation .rb:124:in `block in invoke_all'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/thor-0.14.6/lib/thor/invocation .rb:124:in `each'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/thor-0.14.6/lib/thor/invocation .rb:124:in `map'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/thor-0.14.6/lib/thor/invocation .rb:124:in `invoke_all'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/thor-0.14.6/lib/thor/group.rb:2 26:in `dispatch'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/thor-0.14.6/lib/thor/invocation .rb:109:in `invoke'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/thor-0.14.6/lib/thor/group.rb:2 69:in `block in _invoke_for_class_method'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/thor-0.14.6/lib/thor/shell.rb:7 4:in `with_padding'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/thor-0.14.6/lib/thor/group.rb:2 58:in `_invoke_for_class_method'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/thor-0.14.6/lib/thor/group.rb:1 50:in `_invoke_from_option_orm'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/thor-0.14.6/lib/thor/task.rb:22 :in `run'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/thor-0.14.6/lib/thor/invocation .rb:118:in `invoke_task'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/thor-0.14.6/lib/thor/invocation .rb:124:in `block in invoke_all'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/thor-0.14.6/lib/thor/invocation .rb:124:in `each'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/thor-0.14.6/lib/thor/invocation .rb:124:in `map'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/thor-0.14.6/lib/thor/invocation .rb:124:in `invoke_all'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/thor-0.14.6/lib/thor/group.rb:2 26:in `dispatch'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/thor-0.14.6/lib/thor/base.rb:38 9:in `start'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/railties-3.2.3/lib/rails/genera tors.rb:170:in `invoke'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/railties-3.2.3/lib/rails/comman ds/generate.rb:12:in `<top (required)>'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/activesupport-3.2.3/lib/active_ support/dependencies.rb:251:in `require'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/activesupport-3.2.3/lib/active_ support/dependencies.rb:251:in `block in require'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/activesupport-3.2.3/lib/active_ support/dependencies.rb:236:in `load_dependency'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/activesupport-3.2.3/lib/active_ support/dependencies.rb:251:in `require'         from C:/Ruby193/lib/ruby/gems/1.9.1/gems/railties-3.2.3/lib/rails/comman ds.rb:29:in `<top (required)>'         from script/rails:6:in `require'         from script/rails:6:in `<main>'

I don't know what that means, don't know if is missing something.

Thank you all.