title: Gem Install fails with UnsatisfiableDependencyError
body: <p>I have a puppet module project that fails when trying to update Gems, although it works in some computers. The Gems are used for the spec tests of the module. </p>
  
  <p>Here's the command I run and the output:</p>
  
  <pre><code>X:\puppet-module-rems&gt;gem install -g Gemfile -f
  ERROR:  While executing gem ... (Gem::UnsatisfiableDependencyError)
      Unable to resolve dependency: user requested 'win32-service (= 0.8.7)'
  </code></pre>
  
  <p>The gem that it's trying to install/update is already in the system:</p>
  
  <pre><code>X:\puppet-module-rems&gt;gem list -l
  
  *** LOCAL GEMS ***
  
  ast (2.3.0)
  bigdecimal (1.2.4)
  builder (3.2.2)
  bundler (1.13.0.rc.2)
  childprocess (0.5.9)
  ci_reporter (2.0.0)
  ci_reporter_rspec (1.0.0)
  deep_merge (1.0.1)
  diff-lcs (1.2.5)
  facter (2.4.6 x64-mingw32)
  ffi (1.9.14 x64-mingw32, 1.9.6 x64-mingw32)
  ffi-win32-extensions (1.0.3)
  hiera (1.3.4)
  hiera-eyaml (2.1.0)
  highline (1.6.21)
  io-console (0.4.3, 0.4.2)
  json (1.8.1)
  json_pure (2.0.2)
  metaclass (0.0.4)
  minitar (0.5.4)
  minitest (4.7.5)
  mocha (1.1.0)
  multi_json (1.12.1)
  multi_test (0.1.2)
  parser (2.3.1.2)
  powerpack (0.1.1)
  psych (2.0.5)
  ptools (1.3.3 universal-mingw32)
  puppet (3.8.1 x64-mingw32)
  puppet-lint (2.0.2)
  puppet-syntax (2.1.0)
  puppetlabs_spec_helper (1.1.1)
  rainbow (2.1.0)
  rake (10.1.0)
  rdoc (4.1.0)
  rspec (3.5.0, 3.5.0.beta2)
  rspec-core (3.5.2, 3.5.0.beta2)
  rspec-expectations (3.5.0, 3.5.0.beta2)
  rspec-mocks (3.5.0, 3.5.0.beta2)
  rspec-puppet (2.4.0, 2.3.2)
  rspec-support (3.5.0, 3.5.0.beta2)
  rubocop (0.42.0)
  ruby-progressbar (1.8.1)
  stomp (1.3.3)
  sys-admin (1.6.4)
  test-unit (2.5.5, 2.1.7.0, 2.1.6.0, 2.1.5.0)
  thread_order (1.1.0)
  trollop (2.1.2)
  unicode-display_width (1.1.0)
  win32-dir (0.4.9)
  win32-eventlog (0.6.6, 0.6.2)
  win32-file (0.8.1)
  win32-file-stat (1.5.5)
  win32-process (0.7.5, 0.7.4)
  win32-security (0.2.5)
  win32-service (0.8.7, 0.8.6)
  </code></pre>
  
  <p>Here's the version of ruby I have:</p>
  
  <pre><code>X:\puppet-module-rems&gt;ruby --version
  ruby 2.1.7p400 (2015-08-18 revision 51632) [x64-mingw32]
  </code></pre>
  
  <p><strong>EDITED #1</strong></p>
  
  <p>Here's the content of the Gemfile:</p>
  
  <pre><code>source 'https://rubygems.org'
  
  puppetversion = ENV.key?('PUPPET_VERSION') ? "= #{ENV['PUPPET_VERSION']}" :    ['3.8.1']
  gem 'puppet', puppetversion
  gem 'puppetlabs_spec_helper', '= 1.1.1'
  gem 'puppet-lint', '&gt;= 0.3.2'
  gem 'facter', '&gt;= 1.7.0'
  gem 'ci_reporter_rspec'
  gem 'win32-service', '= 0.8.7'
  gem 'rake', '= 10.1.0'
  gem 'rspec-core', '= 3.5.2'
  gem 'rspec-expectations', '= 3.5.0'
  gem 'rspec-mocks', '= 3.5.0'
  gem 'rspec-puppet', '= 2.4.0'
  gem 'rspec-support', '= 3.5.0'
  </code></pre>