We always use the latest stable PHP version by default. If your site requires a specific version of PHP you can simply use the "Select PHP Version" button in your hosting cpanel.
The PHP development team officially ended support for PHP 4 on December 31st, 2007 and security updates ceased in August of 2008. We strongly advise you to upgrade to the latest stable version for performance and security reasons.
If selecting the PHP version in your cPanel does not work, you can also add one of the following lines to your ".htaccess" file:
To use PHP 5.2 :
- AddHandler application/x-httpd-php52 .php
To use PHP 5.4 :
- AddHandler application/x-httpd-php54 .php
To check if your site will function with PHP 5 before PHP 4 support is removed, simply remove the following line from any ".htaccess" files on your account to immediately switch to PHP 5 (warning: doing so may cause your site to break if it's not compatible):
- AddHandler application/x-httpd-php4 .php