title: Error occurred while installing rmagick
body: <p>I'm getting following error while trying to install Redmine on Windows Server 2008 R2.</p>
  
  <pre><code>C:\Ruby\Apps\Redmine&gt;rake db:migrate
  ←[31mCould not find gem 'rmagick (&gt;= 2.0.0) x86-mingw32' in the gems available o
  n this machine.←[0m
  ←[33mRun `bundle install` to install missing gems.←[0m
  
  C:\Ruby\Apps\Redmine&gt;bundle install
  Fetching gem metadata from http://rubygems.org/.......
  Using rake (0.9.2.2)
  Using i18n (0.6.1)
  Using multi_json (1.3.6)
  Using activesupport (3.2.8)
  Using builder (3.0.0)
  Using activemodel (3.2.8)
  Using erubis (2.7.0)
  Using journey (1.0.4)
  Using rack (1.4.1)
  Using rack-cache (1.2)
  Using rack-test (0.6.2)
  Using hike (1.2.1)
  Using tilt (1.3.3)
  Using sprockets (2.1.3)
  Using actionpack (3.2.8)
  Using mime-types (1.19)
  Using polyglot (0.3.3)
  Using treetop (1.4.10)
  Using mail (2.4.4)
  Using actionmailer (3.2.8)
  Using arel (3.0.2)
  Using tzinfo (0.3.33)
  Using activerecord (3.2.8)
  Using activeresource (3.2.8)
  Using bundler (1.2.1)
  Using coderay (1.0.7)
  Using fastercsv (1.5.5)
  Using rack-ssl (1.3.2)
  Using json (1.7.5)
  Using rdoc (3.12)
  Using thor (0.16.0)
  Using railties (3.2.8)
  Using jquery-rails (2.0.3)
  Using metaclass (0.0.1)
  Using mocha (0.12.3)
  Using mysql (2.8.1)
  Using net-ldap (0.3.1)
  Using pg (0.14.1)
  Using ruby-openid (2.1.8)
  Using rack-openid (1.3.1)
  Using rails (3.2.8)
  Installing rmagick (2.13.1) with native extensions
  Gem::Installer::ExtensionBuildError: ERROR: Failed to build gem native extension
  .
  
          C:/Ruby187/bin/ruby.exe extconf.rb
  checking for Ruby version &gt;= 1.8.5... yes
  Invalid drive specification.
  Unable to get ImageMagick version
  *** extconf.rb failed ***
  Could not create Makefile due to some reason, probably lack of
  necessary libraries and/or headers.  Check the mkmf.log file for more
  details.  You may need configuration options.
  
  Provided configuration options:
          --with-opt-dir
          --without-opt-dir
          --with-opt-include
          --without-opt-include=${opt-dir}/include
          --with-opt-lib
          --without-opt-lib=${opt-dir}/lib
          --with-make-prog
          --without-make-prog
          --srcdir=.
          --curdir
          --ruby=C:/Ruby187/bin/ruby
  
  
  Gem files will remain installed in C:/Ruby187/lib/ruby/gems/1.8/gems/rmagick-2.1
  3.1 for inspection.
  Results logged to C:/Ruby187/lib/ruby/gems/1.8/gems/rmagick-2.13.1/ext/RMagick/g
  em_make.out
  An error occurred while installing rmagick (2.13.1), and Bundler cannot continue
  .
  Make sure that `gem install rmagick -v '2.13.1'` succeeds before bundling.
  </code></pre>
  
  <hr>
  
  <p>On trying to install rmagick using this gem install rmagick -v '2.13.1'</p>
  
  <p>I'm getting this error...</p>
  
  <pre><code>C:\Ruby\Apps\Redmine&gt;gem install rmagick -v 2.13.1
  Temporarily enhancing PATH to include DevKit...
  Building native extensions.  This could take a while...
  ERROR:  Error installing rmagick:
          ERROR: Failed to build gem native extension.
  
          C:/Ruby187/bin/ruby.exe extconf.rb
  checking for Ruby version &gt;= 1.8.5... yes
  Invalid drive specification.
  Unable to get ImageMagick version
  *** extconf.rb failed ***
  Could not create Makefile due to some reason, probably lack of
  necessary libraries and/or headers.  Check the mkmf.log file for more
  details.  You may need configuration options.
  
  Provided configuration options:
          --with-opt-dir
          --without-opt-dir
          --with-opt-include
          --without-opt-include=${opt-dir}/include
          --with-opt-lib
          --without-opt-lib=${opt-dir}/lib
          --with-make-prog
          --without-make-prog
          --srcdir=.
          --curdir
          --ruby=C:/Ruby187/bin/ruby
  
  
  Gem files will remain installed in C:/Ruby187/lib/ruby/gems/1.8/gems/rmagick-2.1
  3.1 for inspection.
  Results logged to C:/Ruby187/lib/ruby/gems/1.8/gems/rmagick-2.13.1/ext/RMagick/g
  em_make.out
  </code></pre>