Troubleshooting SSL
If you encounter errors or issues while working with SSL on your WHMCS installation, see the sections below to start troubleshooting and resolve the issue.
- For information about issues with the SSL certificates that you sell through MarketConnect, see Troubleshooting MarketConnect.
- For general steps to troubleshoot problems in WHMCS, see Start Troubleshooting.
General Issues and Errors
You may encounter the following common issues:
| Error or Issue | Cause | Next Steps |
Website SSLA Certificate Authority verified SSL certificate was not detected on https://www.example.com. This will prevent some features, such as OpenID Connect, from functioning. This may also affect your ability to receive PCI or other accreditation. | An SSL certificate is not configured correctly. | Certificate Not Detected Errors |
curl: (51) SSL: certificate subject name '*.example.net' does not match target host name 'example.com' or curl --max-time 10 -v https://example.com | This error indicates a cURL connection issue. | Certificate Subject Mismatch Errors |
Error: failed to open stream: operation failed | The application is unable to confirm the validity of the SSL certificate. | File Download Errors |
You are currently accessing the admin area using an insecure connection. We recommend using SSL encryption (https) for security. If you don't yet have an SSL Certificate, you can buy one here | You are using an insecure http connection to access the Admin Area and the WHMCS System URL setting contains the http:// prefix instead of https://. | Insecure Connection SSL Errors |
Certification Error - Invalid or Corrupt Certificate | An SSL certificate file is corrupt or contains invalid content. | Invalid or Corrupt Certificate Errors |
| You see SSL-related error messages while attempting to connect to the WHMCS licensing server. | Your CA bundle files are missing or out of date. | Outdated root CA Bundles |
| The system will not connect to PayPal® correctly. | Some PayPal payment gateway modules require an HTTPS-secured connection. | PayPal SSL Errors |
Error code 35 Unknown SSL protocol or Unsupported SSL protocol or sslv3 alert handshake failure or tlsv1 alert protocol version | The server is attempting a secure connection using an outdated SSL protocol. | Unsupported Protocol Errors |
Last modified: 2025 January 29