title: PHP Header() function not redirecting
body: <p>I've got a problem with the header function</p>
  
  <pre><code>if ( ! isset($_SESSION['user']) ) {
  
     header('Location: login.php');
  
  }
  </code></pre>
  
  <p>There is no echo before the if, the page is empty!</p>
  
  <p>it doesn't redirect me. I've <code>var_dump();</code>'ed something in the If statement and it worked so the if is correct.</p>
  
  <p>The php version is 5.6</p>