If you are using symfony or Zend Framework, most probably you are using a .htaccess file indicating apache to direct all requests for non existing files to the symfony or ZF bootstrapper which is usually index.php in the web root.
If you get the above error, it is mostly probably that your .htaccess file is not being read. This is due to the fact that Apache by default does not read this files because of the AllowOverride set to none.
To fix the problem, edit the file httpd.conf and add the following section to your Virtual Host:
Then restart Apache.
This does not apply to shared hosting since on shared servers .htaccess is enabled. Contact us for help in this case.