Rails - A server is already running
<p>I have a problem when I want to start my server in my terminal I do <code>rail s</code> or <code>rails server</code> and there is an error <code>A server is already running. Check /Users/baptiste/code/BaptisteB/my-app/tmp/pids/server.pid.</code></p>

<p>What does it mean? And why it is present? </p>

<p>I delete it and when I check my <code>localhost:3000</code>. There is nothing. I have to log off my laptop and turn on it to begin to work.</p>

<p>How could I stop this error? Maybe I can destroy it with a command. Thank you for your help.</p>