title: Docker - Bind for 0.0.0.0:4000 failed: port is already allocated
body: <p>I am using docker for the first time and I was trying to implement this -
  <a href="https://docs.docker.com/get-started/part2/#tag-the-image" rel="noreferrer">https://docs.docker.com/get-started/part2/#tag-the-image</a></p>
  <p>At one stage I was trying to connect with localhost by this command -</p>
  <pre><code>$ curl http://localhost:4000
  </code></pre>
  <p>which showed this error-</p>
  <pre><code>curl: (7) Failed to connect to localhost port 4000: Connection refused
  </code></pre>
  <p>However, I have solved this by following code -</p>
  <pre><code>$ docker-machine ip default
  $ curl http://192.168.99.100:4000
  </code></pre>
  <p>After that everything was going fine, but in the last part, I was trying to run the app by using following line according to the tutorial...</p>
  <pre><code>$ docker run -p 4000:80 anibar/get-started:part1
  </code></pre>
  <p>But, I got this error</p>
  <pre><code>C:\Program Files\Docker Toolbox\docker.exe: Error response from daemon: driver failed programming external connectivity on endpoint goofy_bohr (63f5691ef18ad6d6389ef52c56198389c7a627e5fa4a79133d6bbf13953a7c98): Bind for 0.0.0.0:4000 failed: port is already allocated.
  </code></pre>