title: How do I open a port in Windows 10 for use?
body: <p>I need to open port#42474 on my Windows 10 system for penetration testing purposes.</p>
  
  <p>I added it to the inbound list of my Windows Defender Firewall (both TCP and UDP protocol), and it is enabled.
  However, whenever I am trying to ping this port on my machine using telnet it is throwing an error as</p>
  
  <blockquote>
    <p>Connecting To localhost...Could not open connection to the host, on port 42474: Connect failed</p>
  </blockquote>
  
  <p>I am able to use telnet to ping other sites such as google.com. But not this port on my machine. Below is the command I am running to test the port and the error:</p>
  
  <p><a href="https://i.stack.imgur.com/jjOWQ.jpg" rel="nofollow noreferrer">Port</a>
  <a href="https://i.stack.imgur.com/4YiAe.jpg" rel="nofollow noreferrer">Telnet error</a></p>
  
  <pre><code>telnet localhost 42474
  </code></pre>
  
  <ol>
  <li>Do I need to do anything else to open port#42474?</li>
  <li>How do I verify if this port is available for use?</li>
  </ol>