Hi @greglfb
Create in a root of site the file info.php with single line <?php phpinfo(); ?>. Open it in you browser, like http://your-site-domain.com/info.php. In a header you will see something like this PHP 5.6.32
If you will see version below 5.3 then you using very outdated PHP version. The autoload.php works perfect start from 5.3 and above. You can see the “End of life” table of PHP versions in this table http://php.net/eol.php
