title: Why do I get an authorization error from Docker when I'm trying to pull a public image?
body: <p>When I tried to run</p>
  
  <pre><code>$ docker run -it ubuntu /bin.bash
  </code></pre>
  
  <p>I got the following error:</p>
  
  <pre><code>Unable to find image 'ubuntu:latest' locally
  docker: Error response from daemon: Get https://registry-1.docker.io/v2/library/ubuntu/manifests/latest: unauthorized: incorrect username or password.
  See 'docker run --help'.
  </code></pre>
  
  <p>Why am I getting an auth error when the <code>ubuntu</code> image is public?</p>