I've just begun developing and I have a working page with a header and body, but I want to start splitting up all of the code by type. I have successfully pulled out the css and javascript but I haven't been able to pull out my header. Right now my files look like this:

index.php:

```
<!DOCTYPE html>
<html>
  <head>
     Some Stuff Here
     <link rel="stylesheet" href="style1.css">
  </head>
  <body>
     <?php include("header.html");?>
     Some Stuff Here
  </body>
</html>

```

header.html:

```
<!DOCTYPE html>
<html>
  <head>
    <link rel="stylesheet" href="style2.css">
  </head>
  <body>
    <script src="header.js"></script>   
    Some Stuff Here
  </body>
</html>

```

When I load index.php in my browser I get the body and its styling, but the header is absent. What's up with me here? 

/\* EDIT \*/

Interestingly I have found that when I load the page from my Synology DS713+ NAS (on which MySQL and phpMyAdmin are installed) the page loads the header just fine, but on my thinkpad (on which I use XAMPP) the page does not add the header. This solves the problem for me since my production environment is my NAS, but perhaps someone can provide an answer for why this might happen.