Seeing the message “There has been a critical error on this website” can be terrifying. You are locked out of your dashboard, your visitors see a white screen, and your business is effectively offline.
Fortunately, this error simply means there is a fatal PHP issue happening behind the scenes—usually caused by a bad plugin update, a theme conflict, or exhausted server memory. Here is how to diagnose and fix it step-by-step.Step 1: Enable WP_DEBUG to Find the Culprit
WordPress hides the actual error message for security reasons. To fix the issue, we need to see what is actually breaking.- Log into your server via FTP or your hosting cPanel File Manager.
- Locate the
wp-config.phpfile in your root directory. - Find the line that says:
define( 'WP_DEBUG', false ); - Change it to:
define( 'WP_DEBUG', true ); - Save the file and refresh your broken website.
Step 2: Disable the Problematic Plugin via FTP
If the error message names a specific plugin (e.g.,/wp-content/plugins/woocommerce/...), you can disable it without dashboard access.- Navigate to the
/wp-content/plugins/directory using FTP. - Find the folder of the plugin mentioned in the error.
- Rename the folder (e.g., change
woocommercetowoocommerce-disabled). - Refresh your site. WordPress will automatically deactivate the plugin and your site should load.
Step 3: Increase PHP Memory Limit
Sometimes, the critical error is simply your server running out of memory while running a heavy process.Open yourwp-config.php file again and paste this line just above the “That’s all, stop editing!” message:define( 'WP_MEMORY_LIMIT', '256M' );