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.

Installation Issues

You may encounter the following common issues:

Error or IssueExplanationNext 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 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.
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 valueYou attempted to install WHMCS with MySQL Strict Mode enabled.Field Default Value Errors

Last modified: May 28, 2024