title: NPM throws error unable_to_get_issuer_cert_locally while installing any package behind corporate firewall
body: <p>1.I downloaded node ( latest v4.6.0)</p>
  
  <ol start="2">
  <li>Set proxy path FOR npm</li>
  <li>tried npm install</li>
  <li>I got the error ---
        UNABLE_TO_GET_ISSUER_CERT_LOCALLY<a href="https://i.stack.imgur.com/sCG3d.png" rel="noreferrer"><img src="https://i.stack.imgur.com/sCG3d.png" alt="enter image description here"></a></li>
  </ol>