title: Gem::RemoteFetcher::FetchError with gems.github.com
body: <p>I got an error with:</p>
  
  <pre><code>ruby 2.5.1p57 (2018-03-29 revision 63029) [x86_64-linux]
  </code></pre>
  
  <p>When I tried to install the bundler:</p>
  
  <pre><code>gem install bundler
  </code></pre>
  
  <p>The error:</p>
  
  <pre><code>ERROR:  While executing gem ... (Gem::RemoteFetcher::FetchError)
      bad response Forbidden 403 (http://gems.github.com/quick/Marshal.4.8/bundler-0.3.0.gemspec.rz)
  </code></pre>
  
  <p>I solved momentarily with this command:</p>
  
  <pre><code> gem sources --remove "http://gems.github.com"
  </code></pre>
  
  <p>Because it is 403 Forbidden problem.
  Idea from: <a href="https://stackoverflow.com/questions/23351405/getting-a-while-executing-gem-gemremotefetcherfetcherror-503-error-whe">Getting a While executing gem ... (Gem::RemoteFetcher::FetchError) 503 error when attempting to install rails</a></p>
  
  <p>Any ideas how to solve or why this error occurs. </p>