title: cannot install ruby gems - zlib error
body: <p>I'm trying to install some Ruby Gems so I can use Ruby to notify me when I get twitter messages. However, after doing a <code>gem update --system</code>, I now get a zlib error every time I try and do a <code>gem install</code> of anything. below is the console output I get when trying to install ruby gems. (along with the output from <code>gem environment</code>).</p>
  
  <pre><code>C:\data\ruby&gt;gem install twitter
  ERROR:  While executing gem ... (Zlib::BufError)
      buffer error
  
  C:\data\ruby&gt;gem update --system
  Updating RubyGems
  ERROR:  While executing gem ... (Zlib::BufError)
      buffer error
  
  C:\data\ruby&gt;gem environment
  RubyGems Environment:
    - RUBYGEMS VERSION: 1.2.0
    - RUBY VERSION: 1.8.6 (2007-03-13 patchlevel 0) [i386-mswin32]
    - INSTALLATION DIRECTORY: c:/ruby/lib/ruby/gems/1.8
    - RUBY EXECUTABLE: c:/ruby/bin/ruby.exe
    - EXECUTABLE DIRECTORY: c:/ruby/bin
    - RUBYGEMS PLATFORMS:
      - ruby
      - x86-mswin32-60
    - GEM PATHS:
       - c:/ruby/lib/ruby/gems/1.8
    - GEM CONFIGURATION:
       - :update_sources =&gt; true
       - :verbose =&gt; true
       - :benchmark =&gt; false
       - :backtrace =&gt; false
       - :bulk_threshold =&gt; 1000
    - REMOTE SOURCES:
       - http://gems.rubyforge.org/
  </code></pre>