The “cURL error 28: Connection timed out” may appear during update key activation, verification, deactivation within Gpl WordPress Update Manager, or while updating plugins and themes.

WordPress relies on the wp_remote_post() function (based on cURL) to communicate with external servers. This process is required to validate update keys and retrieve updates.

For this system to work correctly, your website must be able to send requests to our server and receive a response. If this communication fails, the request times out and the error is triggered.

In most cases, this indicates that outgoing connections from your server are being blocked or limited, often due to firewall rules or server-side security configurations.

Troubleshooting steps

Start by reviewing the following checks. Your hosting provider should be able to assist with most of them:

• Ensure your server is running an up-to-date version of PHP and the cURL library
• Increase your PHP memory limit
• Increase the cURL timeout value
• Verify with your hosting provider that wp-cron is working correctly and loopback requests are enabled
• Check for firewall restrictions or security modules (such as mod_security) that may block outgoing requests
• Install the Query Monitor plugin and review HTTP API calls on the page where the error appears

If the issue persists

If the steps above do not resolve the problem, contact your hosting provider and ask them to confirm that your server can establish outbound cURL connections without restrictions.
Once confirmed, you can reach out and provide your server’s IP address. A check can then be performed to ensure it is not being blocked, although this is a rare occurrence since the server regularly processes a high volume of cURL requests successfully.

Additional resources

This article contains further details about this specific error and may help you or your hosting provider identify the root cause.