Login via SSH to the server and run the following commans to find out which PHP and Apache modules are installed.
Apache:
/usr/local/apache/bin/httpd -l
PHP:
php -v
If the module you're looking for is not listed you'll need to run a recompile to have the module installed.
On cPanel servers you can run the following command.
/scripts/easyapache
If you're unfamiliar with the above process then contact WebGo support for further assistance.