I get this warning while installing xf 1.3 Your server is running an outdated and unsupported version of PHP (5.2.17). If possible, you should upgrade to PHP 5.4 or 5.5. So I goes to my cpanel and it's running PHP 5.2 (Single php.ini) Same as PHP 5.2, but all subdirectories will use ~/public_html/php.ini yeah I can change to 1) PHP 5.4 All files with the extension .php will be handled by the PHP 5.4 engine. 2)PHP 5.4 (Single php.ini) Same as PHP 5.4, but all subdirectories will use ~/public_html/php.ini 3)PHP 5.4 (FastCGI) All files with the extension .php will be handled by PHP 5.4 FastCGI processes. FastCGI for PHP makes all your PHP applications run through mod_fastcgi instead of mod_suphp. This eliminates the overhead of loading the PHP interpreter on every hit. Since it is always in memory ready for the next hit, the responses will be generated faster. I don't understand any of this. I take it everything I have installed, stores program, Joomla and current xf 1.2.4 forums are running this 5.2 (single php.ini What happens to those if I change to another php version? Will the current programs crash?