How to Fix a WordPress 500 Internal Server Error

A 500 Internal Server Error means the server hit a problem and couldn’t say what it was. That vagueness is why it’s frustrating: the message tells you nothing, but the cause is almost always one of a short list of things. Work through them in order and you’ll usually find it quickly.

Short answer: to fix a WordPress 500 error, check the server error log, rename .htaccess to regenerate it, raise the PHP memory limit, deactivate all plugins to find a conflict, switch to a default theme, confirm your PHP version is supported, and if needed replace core files with a fresh copy.

What causes a 500 error in WordPress?

The error is a generic server response, not a WordPress-specific message. In WordPress the usual causes are:

Step 1: Read the error log first

Guessing wastes time when the server often records the real error. Check your host’s control panel for an error log (in cPanel it’s under Metrics → Errors), or look for an error_log file in your site directory.

You can also have WordPress write its own log. Add these lines to wp-config.php, above the line that says to stop editing:

define('WP_DEBUG', true); define('WP_DEBUG_LOG', true); define('WP_DEBUG_DISPLAY', false);

Errors are then saved to wp-content/debug.log. The file path in a fatal error usually names the plugin or theme at fault. Turn debugging off again when you’re done.

Step 2: Regenerate your .htaccess file

Using FTP or your host’s file manager, rename .htaccess in the site root to .htaccess_old, then reload the site. If it comes back, log in to the dashboard and go to Settings → Permalinks and click Save Changes to generate a fresh file.

This applies to Apache and LiteSpeed servers. Nginx doesn’t use .htaccess, so skip this step there.

Step 3: Increase the PHP memory limit

If the log mentions “allowed memory size exhausted”, add this to wp-config.php:

define('WP_MEMORY_LIMIT', '256M');

Your host can cap this regardless of what you set. If the error persists or the limit won’t change, ask the host to raise it.

Step 4: Deactivate plugins to find a conflict

If you can’t reach the dashboard, use FTP to rename wp-content/plugins to plugins_old. If the site loads, a plugin is responsible.

1. Rename the folder backRestore the name plugins. All plugins will show as deactivated.
2. Reactivate one at a timeStart with the plugins you updated most recently.
3. Reload after each oneWhen the error returns, you’ve found the culprit.
4. Replace or remove itUpdate it, contact its developer, or switch to an alternative.

With WP-CLI installed, wp plugin deactivate --all does the same in one command.

Step 5: Switch to a default theme temporarily

Rename your active theme’s folder inside wp-content/themes. WordPress will fall back to a default theme such as Twenty Twenty-Four, provided one is installed. If the error disappears, the problem lies in your theme or its custom code.

Step 6: Confirm the PHP version is supported

Check which PHP version your host runs and which versions your plugins and theme support. A newly upgraded PHP version can break older code, while very old versions can fail with current plugins. Most hosts let you switch versions in the control panel, so you can roll back to confirm.

Step 7: Replace core files if nothing else works

Download a fresh copy of WordPress from wordpress.org and upload the wp-admin and wp-includes folders over your existing ones. Don’t touch wp-content or wp-config.php, because those hold your content and settings.

While you’re there, check permissions. Folders are typically 755 and files 644.

When to ask your host or a developer

Contact your host if the log shows server-level errors, resource limits or a ModSecurity block you can’t edit. Involve a developer if the log points to custom code, if you don’t have a recent backup, or if the site is revenue-critical.