title: How to fix error "ionic-app-scripts has unexpectedly closed (exit code 1)."
body: <p>I am working with ionic and my <code>ionic serve</code> usually run just fine. Now i want to run an old project but <code>ionic serve</code> throws error, showing below error</p>
  
  <blockquote>
    <p>[ERROR] ionic-app-scripts has unexpectedly closed (exit code 1).</p>
  </blockquote>
  
  <pre><code>    The Ionic CLI will exit. Please check any output above for error details.
  </code></pre>