title: PHP - include() or require() with relative paths won't work on windows, even when appending __DIR__
body: <p>I was reading here about problems in PHP when using include() or required() with relative paths and all the solutions I saw was to append <strong>DIR</strong></p>
  
  <p>I'm currently working on Windows, and even though the error message displays the current value of <strong>DIR</strong>, then the relative path seems to be added as a string, rather than going one level up, for example:</p>
  
  <pre><code>include(__DIR__ . "..\\another_folder\\file_2.php");
  </code></pre>
  
  <p>produces the following error:
      Warning: include(C:\xampp\htdocs\main_folder..\another_folder\file_2.php) [function.include]: failed to open stream: No such file or directory in </p>
  
  <p>Any idea what's going on?</p>