title: Error occured while trying to proxy Angular2 CLI, Node.js, Socket.io
body: <p>I am getting error after I stop my application. How can I fix this issue?
  For production I am using port 3000 and for development 4200.</p>
  
  <blockquote>
    <p>[HPM] Error occurred while trying to proxy request
    /socket.io/?EIO=3&amp;transport=polling&amp;t=LhNBrs9&amp;sid=CUdJnCGXlmH0WGSyAAAA
    from localhost:4200 to <a href="http://localhost:3000" rel="nofollow noreferrer">http://localhost:3000</a> (ECONNRESET)
    (<a href="https://nodejs.org/api/errors.html#errors_common_system_errors" rel="nofollow noreferrer">https://nodejs.org/api/errors.html#errors_common_system_errors</a>)</p>
  </blockquote>
  
  <p>My procy.conf looks like this:</p>
  
  <p><strong>proxy.conf.json</strong></p>
  
  <pre><code>{
    "/": {
      "target": "http://localhost:3000",
      "secure": false
    }
  
  }
  </code></pre>