title: Windows Process from PID
body: <p>I'm trying to determine which application or system program is using a particular port on a Windows 2008 R2 machine.</p>
  
  <p>I've run </p>
  
  <pre><code>netstat -a -n -o
  </code></pre>
  
  <p>And have determined that PID is holding open port 445, which I'm interested in.</p>
  
  <p>But when I run <code>tasklist</code> or Microsoft's pslist program, it tells me that the process holding the port open is simply named 'Sys'.</p>
  
  <p>Is there another tool or approach I can use to find which is the real process holding it open?</p>