How to Fix
5xx Server Errors

Regenerate Your .htaccess File

A corrupted .htaccess file is the #1 cause of the 500 error in WordPress.

1. Access your site using FTP or your host's File Manager.
2. Find the .htaccess file in the root folder (where your wp-content folder is). You may need to enable "Show hidden files".
3. Rename the file to .htaccess_old.
4. Try reloading your website. If it works, the file was corrupted.

To generate a new, clean .htaccess file, simply log into your WordPress admin, go to Settings > Permalinks, and click the Save Changes button without altering anything.

Check File and Folder Permissions

Incorrect permissions can stop the server from executing scripts. Your files and folders must follow standard WordPress security permissions.

• Folders should be set to 755 or 750.
• Files should be set to 644 or 640.
• wp-config.php can be set to 440 or 400 for extra security.

Disable Problematic Plugins

If a plugin contains a "heavy" script (like a massive database query) that gets stuck in an infinite loop, your server will eventually throw a 503 error as it runs out of PHP workers.

1. Connect to your site via FTP.
2. Navigate to /wp-content/ and rename the plugins folder to plugins_old.
3. If the site loads again, rename the folder back to plugins and start deactivating them one by one to find the culprit.

Limit the WordPress Heartbeat API

The Heartbeat API sends continuous requests to the server while you are logged into the dashboard (for autosaving, post locking, etc.). If you leave your dashboard open in a tab, this can simulate a DDoS attack and cause a 503 error.

You can limit or disable the Heartbeat API by adding this code to your theme's functions.php file:

add_action( 'init', 'stop_heartbeat', 1 );
function stop_heartbeat() {
    wp_deregister_script('heartbeat');
}