Enabling WP_DEBUG

When debugging issues on your WordPress.com site, it’s often useful to enable the built in debugging mode available to WordPress.

Before you enable WP_DEBUG

By default, any web server or PHP errors or warnings for your site are automatically logged and available from your site’s Settings page. You can learn how to access and download these logs in the Site Monitoring documentation under Access logs.

You can still enable WP_DEBUG, but please note that doing so may cause excessive warnings and break the default logging WordPress.com provides. It may also cause excessive disk usage if it’s not disabled and the debug.log file deleted after using it.

Enable WP_DEBUG

To activate debugging mode, take the following steps:

1. Connect to your WordPress site using your preferred SFTP client.
2. Once connected, locate the wp-config.php file in the root directory of your WordPress installation.
3. Open the wp-config.php file in your text editor.
4. Find the section titled For developers: WordPress debugging mode.
5. Update the code to look like this:

if ( ! defined( 'WP_DEBUG') ) {
	define( 'WP_DEBUG', true );
	if ( WP_DEBUG ) {
		define( 'WP_DEBUG_DISPLAY', false );
		define( 'WP_DEBUG_LOG', true );
	}
}

6. Save the changes you made to the wp-config.php file.

This will enable debug mode, prevent any logging from being displayed on the front end, and log any errors or calls to error_log to a debug.log file.

You can read more about these settings, as well as additional debugging settings you can enable the WordPress Advanced Administration Handbook

Retrieve logs

Now you’ve enabled debug mode, you can retrieve the logs to help diagnose issues:

1. Reconnect to your WordPress site using SFTP.
2. Navigate to the wp-content directory and locate the debug.log file.
3. Download or view the debug.log file. You can download the debug.log file to your computer or view it directly using a text editor.

Disable WP_DEBUG

To prevent performance issues and keep sensitive information secure, it’s important to disable debugging mode in your production environment after you’ve finished debugging.

Once you’ve finished debugging, disable WP_DEBUG with the following steps:

1. Reconnect to your WordPress site again with SFTP.
2. Locate the wp-config.php file in the root directory of your WordPress installation.
3. Open the wp-config.php file in your text editor.
4. Find the section titled For developers: WordPress debugging mode.
5. Update the code to look like this:

if ( ! defined( 'WP_DEBUG') ) {
	define( 'WP_DEBUG', false );
}

6. Save the changes you made to the wp-config.php file.