Troubleshooting Installation
If you encounter errors or issues while installing WHMCS, see the sections below to start troubleshooting and resolve the issue.
- For more information, see Getting Started with WHMCS and Install WHMCS.
- For general steps to troubleshoot problems in WHMCS, see Start Troubleshooting.
Installation Issues
You may encounter the following common issues:
| Error or Issue | Explanation | Next Steps |
|---|---|---|
After entering your WHMCS license key and database connection details, you see a A license key is required. If you don't have one, please visit www.whmcs.com to purchase one error on Step 3. | There is an issue with the PHP sessions configuration in your server environment. | License Key Required Errors |
| The installation process became stuck on Step 4. | This issue usually occurs because your system does not meet our system requirements. The most common problem is that your PHP memory_limit value is less than 64 MB. | Make certain that your PHP configuration and all other aspects of your system meet the system requirements, and then retry installation. For more information, see system requirements. |
Oops! error during Step 4.or SQLSTATE[23000]: Integrity constraint violation: 1062 Duplicate entry '1' for key 'tblconfiguration.PRIMARY' appears in the tblerrorlog table of WHMCS’s MySQL® database. | You have initiated the installation process twice simultaneously, causing the system to attempt to write duplicate data to the MySQL database. | Duplicate tblconfiguration Errors |
Field xxx doesn't have a default value | You attempted to install WHMCS with MySQL Strict Mode enabled. | Field Default Value Errors |
Last modified: January 8, 2025