Troubleshooting Licensing
If you encounter errors or issues while authenticating with WHMCS, see the sections below to start troubleshooting and resolve the issue.
- For help troubleshooting issues with the cPanel Licensing Addon, see Troubleshooting Addon Modules.
- For help troubleshooting licensing issues with hosting control panels, see Troubleshooting Server Issues.
- For general steps to troubleshoot problems in WHMCS, see Start Troubleshooting.
Licensing Errors
You may encounter the following common issues:
| Error or Issue | Cause | Next Steps |
Curl Error - Couldn't connect to host (7) or Server Command Error - Curl Error - Couldn't connect to host (7) or Curl Error: Connection refused - Code 7 | Your firewall is blocking a necessary port. | cURL Couldn't Connect to Host Errors |
Curl Error - Couldn't resolve host (6) or Server Command Error - Curl Error - Couldn't resolve host (6) | Your firewall is blocking a necessary port. | cURL Couldn't Resolve Host Errors |
Your license key is invalid | You performed a required license check from a non-web context. | Invalid License API Errors |
License Invalid | You entered an invalid license key or moved the WHMCS installation without updating the license. | Invalid License Errors |
Invalid License (on HostGator) | HostGator made mass changes to one or more directories. | Invalid Licenses on HostGator |
A license key is required. If you don't have one, please visit www.whmcs.com to purchase one. | There is an issue with the PHP sessions configuration in your server environment. | License Key Required Errors |
No Connection | There is a problem preventing your server from communicating with the WHMCS licensing server. | No Connection 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 | Your CA bundle files are missing or out of date. | Outdated root CA Bundles |
Last modified: 2025 February 6