PHP.ini file changes not taking effect

My website is getting the error :

Fatal error: Class 'XSLTProcessor' not found

I fixed this on my localhost (XAMP) by un-commenting the line :

extension=php_xsl.dll

This worked for localhost. Now i have put the website onto a linux server with GoDaddy, i get the same error.

I have put the same php.ini file from my localhost into the root server and ran phpInfo, which confirms the Loaded Configuration File is coming from the correct php.ini.

So i know that my php.ini settings are correct, and i know that the website is loading the correct php.ini - why is it still not working?

Thanks