title: Can't get last version of NPM working
body: <p>I'm trying to update npm to latest version, since I'm using the 1.4.28.
  Using:</p>
  
  <pre><code>npm update -g npm
  </code></pre>
  
  <p>I get the following output:</p>
  
  <pre><code>npm@1.3.26 C:\Users\ck\AppData\Roaming\npm\node_modules\npm-check-updates\node_modules\npm
  npm@2.1.5 C:\Users\ck\AppData\Roaming\npm\node_modules\ember-cli\node_modules\npm
  </code></pre>
  
  <p>and then running</p>
  
  <pre><code>npm -v
  </code></pre>
  
  <p>I can see that I'm still using the 1.4.28; I can't understand the output I got after trying to update, since it is talking about 1.3.26 and 2.1.5, but I have installed 1.4.28??</p>
  
  <p>I'm on windows and I've already tried to uninstall and reinstall node;</p>