Linux shared hosting allows you run PHP4 or PHP5 on your webspace.

This can be selected from your control panel:

Hosting -> Web Space -> WebSite Administration

If you want to run PHP4, then ensure the 'PHP support' setting is enabled. This will ensure that all files with the extension of .php will be processed by the PHP4 Apache module.

If you want to run PHP5, then ensure the 'PHP5 support' setting is enabled. This will ensure that all files with the extension of .php5 will be processed by the PHP5 FastCGI module.

When both settings are enabled, then .php pages will run PHP4 and .php5 pages will run PHP5.

When only 'PHP5 support' is enabled, then all .php or php5 pages will run as PHP5.

In some unusual situations it can be required that .php pages run as PHP4 on some parts of the website and as PHP5 on others. To achieve this, you should first ensure that both settings are enabled so that by default, .php pages run PHP4. On a per directory basis, you can then override this setting and run PHP5 by creating a .htaccess file containing the following line:

AddHandler php5-cgi-script .php

Please note that this information relates only to Linux Shared Hosting on our Parallels Automation hosting platform.
Older Sphera servers support only PHP4 (so you should request an account migration if you require PHP5).
Windows shared hosting supports only PHP5.