title: could not open connection to the host, on port 23: Connect failed
body: <p>I have extremely simple chat server (100 lines of code on Java) and it is working properly. When I'm testing it with Telnet on localhost everything is just fine. When I asked some of my friends to test it with telnet (<code>telnet &lt;myIP&gt; &lt;port&gt;</code>, the port I assigned is 5555, server is running on my PC with static IP) everything is just fine too, but one of my friends received the error</p>
  
  <blockquote>
    <p>Could not open connection to the host, on port 23: Connect failed</p>
  </blockquote>
  
  <p>when he was trying to connect. Every firewall, anti-virus and anti-spyware software is turned off from both sides. <strong>Why could some of my friends connect but not him? Where is the problem: is it on the server or his PC?</strong></p>