Integrity constraint violation: 1062 Duplicate entry '1' for key 'tblconfiguration.PRIMARY' Errors

Symptom

On step 4 of installation (the install.php page), after entering your WHMCS license key and database connection details, a Oops! Something went wrong and we couldn't process your request message displays.

You may also see an Integrity constraint violation error message in WHMCS or in the tblerrorlog table of WHMCS's MySQL® database:

SQLSTATE[23000]: Integrity constraint violation: 1062 Duplicate entry '1' for key 'tblconfiguration.PRIMARY'

Cause

You have initiated the installation process twice simultaneously, causing the system to attempt to write duplicate data to the MySQL database.

This could be due, for example, to website monitoring tools or other visitors accessing the WHMCS index.php file at the exact moment the installation is in progress.

Solution

To resolve this issue:

  1. Temporarily deactivate monitoring or similar tools that might access the WHMCS directory.
  2. Restrict access to the WHMCS directory from other IP addresses until the installation process is complete. For more information, see Restricting Access by IP Address.
  3. Drop the contents of WHMCS's MySQL database.
  4. Return to the install.php page and start the installation process again.