WHMCS core files are ionCube encoded. Before uploading and installing WHMCS, your server must have the latest ionCube Loader matching your server PHP version, otherwise you will get blank page or fatal PHP error.
Step1: Install latest ionCube Loader
- Confirm your server PHP version first (run php -v via SSH or create phpinfo.php to check).
- cPanel/WHM server method (recommended):Go to WHM → EasyApache, select your active PHP version, find ionCube extension, install and save…