Upgrading to 4.2.3 PHP error

[simon2323]

I am upgrading my forum to 4.2.3 (latest version downloaded today)
followed all directions
uploaded files
when i run install/upgrade.php i get this error :

Due to the following errors, the install/upgrade can not continue:
This version of vBulletin requires PHP version 5.4.0 or greater. Your PHP is version 5.3.29, please ask your host to upgrade.

I went to my host (Glow host) and selected PHP version 5.4 (also have option for 5.5)
then I get ERROR 500 - Internal Server Error

My host (which by the way has a great customer support) says :

"I have checked this and found that script that you are using is working with php version 5.3 only. Please check your scripts with the help of a developer and make sure that your scripts are compatible with upgraded php versions."

I downloaded the scripts today from Vbulletin

Please help, i am at a dead end here

TIA

[kh99]

I went to my host (Glow host) and selected PHP version 5.4 (also have option for 5.5)
then I get ERROR 500 - Internal Server Error

Are you saying you get "Internal Server Error" when you try to run install/upgrade.php after selecting php5.4?

[Trevor Hannant]

If you're getting an Internal Server Error, you'll also be getting a message in your server's error logs (or you should be!). What is that error message?