The Twilio SMS security module for WHMCS requires a specific set of system components to operate correctly and securely. Our developers have tested it exclusively with PHP 5.6 or higher, WHMCS 7.x releases, OpenSSL (or any equivalent SSL library) supporting TLS 1.1 and higher, the IonCube Loader at v10.1.x or above, and the cURL PHP extension also built with TLS 1.1+ support. A Twilio account is mandatory along with at least one SMS-capable phone number provisioned through their service. The module may work under different conditions; however, we have only validated these scenarios and provide support accordingly. Always start from a solid base that already fulfills the WHMCS core system requirements.

It is important to meet these requirements to avoid common problems like SSL handshake failures when the module attempts to send SMS messages, PHP fatal errors from missing functions, or inability to decode the protected module code without the proper IonCube version. The prerequisite knowledge of WHMCS ensures you can handle the integration without needing additional assistance for basic tasks such as file permissions or addon activation. The TLS requirement prevents connection failures to Twilio endpoints that no longer accept outdated protocols.

#System Requirements

  • Clear understanding of using WHMCS as well as uploading, installing and configuring addons and gateways
  • PHP 5.6 or higher
  • WHMCS 7.x (we do not support alpha, beta or release candidate builds)
  • OpenSSL (or any SSL library) w/ TLS 1.1+ support
  • Ioncube loader v10.1.x or higher

#PHP Extension Requirements

  • cURL w/ TLS 1.1+ support

#Twilio Account Requirements

The module uses Twilio to deliver SMS messages as part of the security workflow. Without a functional Twilio integration the SMS portion cannot operate.

  • A Twilio account - If you do not have one, you may signup at twilio.com
  • A Twilio SMS capable phone number

#Testing Your Environment

We offer a PHP script that will quickly and easily check your PHP and WHMCS installation for any missing requirements. The tool can be downloaded here: https://billing.aspnix.com/dl.php?type=d&id=138. Place the script inside your WHMCS root folder and execute it through a browser or from the command line. It will output a report listing each checked item and whether it passes. This script inspects PHP version, loaded extensions, IonCube presence, TLS support in cURL and OpenSSL, and the WHMCS version in use.

bash 
php --version
php -m | grep -E 'curl|openssl'
php -i | grep -E 'ionCube|TLS'

These manual CLI checks provide supporting data points if the test script is unavailable. Compare the output against the stated requirements before attempting installation. Outdated cURL builds that only support TLS 1.0 will fail the TLS checks and block API connectivity.

#Practical Takeaway

Run the requirements test script first to confirm every item passes, then install the module and enter your Twilio credentials inside the WHMCS admin area. This sequence eliminates the majority of deployment errors and lets the SMS security features function immediately after configuration.