Wary about upgrading PHP

[WithoutMotive]

Just come to install something on our web server which requires PHP 5+.
Our website runs with PHP and I've only just noticed that it's down to PHP 4.

Obviously, I want to upgrade to 5 but don't want to mess up our website so I'm a little wary.

Can anyone give me a few pointers to maybe convince myself that it's ok? LOL

[powdarrmonkey]

On one hand, security support for PHP4 is going or if not gone, and you should be working with 5 by now anyway. But on the other, it depends what software you're running on it. You could investigate running them side-by-side so you can test your website and make sure it's all ok before committing to it.

Most functionality is the same. The only way you're going to find out is by taking a backup and trying it one night.