OPcache Warnings

Problem

This troubleshooting information only applies to self-hosted WHMCS installations.

You are experiencing problems that relate to stale cached data or PHP script execution.

For example, you may see the following error while trying to activate the PayPal Payments payment gateway module:

Gateway Activation Failed

You may see an OPcache Status error in the Admin Area or an OPcache Status warning at Configuration () > System Health.

Cause

This warning indicates that the OPcache PHP extension is enabled.

We strongly discourage enabling OPcache on your WHMCS installation’s server.

OPcache can cause serious problems with old data caches that WHMCS cannot control. In some cases, its features can also prevent PHP scripts from running each time that WHMCS executes them. These issues can cause unexpected behavior in WHMCS.

Solution

Deactivate the OPcache extension from your PHP configuration. To do this, use the appropriate feature in your control panel or edit the php.ini file to remove any opcache.enable lines. Then, recompile PHP.

For assistance, see your control panel’s documentation, or contact your hosting provider or system administrator:

Last modified: 2025 December 16