Hi there, I have a customer who have a few customer developed sections on their website that was many years ago now and worked fine running on PHP4. Their hosting provider now let them know that PHP4 will be unsupported soon so they'd have to upgrade to at least 5.4. We did a quick test and it does break most if on PHP 5.4.
I did a couple PHP projects about 10 years ago now so I can help myself but I thought I'd here for some hints of the most important things to change so it will work for 5.4 or later. I found this - http://php.net/manual/en/migration5.incompatible.php
- but their site doesn't do anything fancy, advice for obvious things to check would be very handy thanks!