How to Fix the WordPress 500 Internal Server Error (Complete Guide)

The WordPress 500 internal server error is one of the most common — and most frustrating — problems you can encounter on your website, because it gives you almost no information about what actually went wrong. Instead of your site, visitors see a plain white screen or a generic "500 Internal Server Error" message with no helpful detail. The good news is that this error almost always has a fixable cause, and this guide will walk you through every proven method to resolve it quickly.

What Causes the WordPress 500 Internal Server Error?

Before diving into fixes, it helps to understand what triggers a 500 error. The HTTP 500 status code simply means the server encountered an unexpected condition that prevented it from fulfilling the request. In WordPress, this is almost always caused by one of the following:

• A corrupted or misconfigured .htaccess file — the most common culprit.
• A PHP memory limit that is too low — WordPress or a plugin runs out of memory.
• A faulty plugin or theme — bad code triggers a fatal PHP error.
• Corrupted WordPress core files — usually after a failed update or a hack.
• Server-side issues — database connection problems, misconfigured server software, or resource limits.

Work through the sections below in order. Each fix addresses one of these causes, starting with the simplest and most common.

Fix 1: Regenerate Your .htaccess File

A corrupted .htaccess file is the number-one reason WordPress returns a 500 error. The file sits in the root of your WordPress installation and controls how Apache handles URL rewrites, redirects, and security rules. A single bad character can bring the whole site down.

How to Reset the .htaccess File via FTP or File Manager

1. Connect to your server using an FTP client (such as FileZilla) or your hosting control panel's File Manager.
2. Navigate to the root directory of your WordPress installation (the folder that contains wp-config.php).
3. Locate the file named .htaccess. If you cannot see it, enable hidden files in your FTP client (in FileZilla go to Server > Force Showing Hidden Files).
4. Download a backup copy of the existing .htaccess file to your computer before making any changes.
5. Delete the .htaccess file from the server — or rename it to .htaccess_old.
6. Try loading your website. If the 500 error disappears, the .htaccess file was the problem.
7. Log in to your WordPress admin dashboard, go to Settings > Permalinks, and click Save Changes without changing anything. WordPress will automatically generate a fresh, correct .htaccess file.

What a Correct Default .htaccess Looks Like

If you need to recreate the file manually, paste the following default WordPress content:

# BEGIN WordPress

RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]

# END WordPress

If your WordPress installation lives in a subdirectory (for example, /blog/), change RewriteBase / to RewriteBase /blog/.

Fix 2: Increase the PHP Memory Limit

WordPress needs a certain amount of PHP memory to run. If a plugin, theme, or complex page tries to use more memory than the server allows, PHP will crash and return a 500 error. The WordPress default minimum recommendation is 64 MB, but many modern sites need 256 MB or more.

Method A: Edit wp-config.php

1. Connect to your server via FTP or File Manager.
2. Open the file wp-config.php in the root of your WordPress installation.
3. Add the following line above the line that reads /* That's all, stop editing! Happy publishing. */:

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

4. Save the file and reload your website to see if the error is resolved.

Method B: Edit php.ini or .htaccess

If editing wp-config.php does not work, your host may require the limit to be set at the server level. Add the following line to your .htaccess file or to a php.ini file in your root directory:

php_value memory_limit 256M

Contact your hosting provider if you are on a managed host and cannot edit these files directly — they can raise the limit from the server side.

Fix 3: Deactivate All Plugins

A poorly coded or outdated plugin is one of the most frequent causes of the 500 internal server error, especially after a WordPress core update. Deactivating all plugins at once lets you confirm whether a plugin is responsible before narrowing it down.

Deactivating Plugins When You Cannot Access the Admin Dashboard

If the error prevents you from logging in, you can disable plugins directly via the database or your file system.

1. Connect to your server via FTP or File Manager.
2. Navigate to wp-content/plugins/.
3. Rename the entire plugins folder to something like plugins_disabled. WordPress will no longer find the folder and will automatically deactivate all plugins.
4. Reload your website. If the error is gone, a plugin was to blame.
5. Rename the folder back to plugins.
6. Re-enable plugins one at a time — go to Plugins > Installed Plugins and activate each plugin individually, reloading the site after each one until the error reappears. The last plugin you activated is the problem.
7. Delete or replace the faulty plugin and contact its developer.

Deactivating Plugins via WP-CLI

If you have SSH access, WP-CLI makes this even faster:

wp plugin deactivate --all

Once you have identified the problem plugin, reactivate all others with:

wp plugin activate --all

Fix 4: Switch to a Default WordPress Theme

Your active theme can cause a 500 error in exactly the same way a plugin can — a PHP fatal error in functions.php or a template file will crash the entire site. Switching to a default theme (such as Twenty Twenty-Four) isolates whether the theme is responsible.

Switching Themes When the Dashboard Is Inaccessible

1. Connect via FTP or File Manager and navigate to wp-content/themes/.
2. Rename your active theme's folder (for example, rename my-theme to my-theme-old). WordPress cannot find it and will fall back to the next available theme.
3. If no default theme is installed, upload one from wordpress.org directly into the themes/ folder.
4. Reload your site. If the 500 error disappears, your theme's code is the problem.
5. Contact your theme developer or revert to an earlier version while a fix is prepared.

Fix 5: Enable WordPress Debug Mode to Find the Root Cause

If the steps above have not resolved the error, enabling WordPress debug mode will log the exact PHP error that is causing the crash. This is invaluable for diagnosing less obvious problems.

Turning On Debug Logging in wp-config.php

1. Open wp-config.php via FTP or File Manager.
2. Add or update the following three lines, placing them above the "stop editing" comment:

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

3. Save the file and reload your website to trigger the error.
4. Navigate to wp-content/debug.log — this file now contains the full error message, including the file name and line number responsible.
5. Use that information to pinpoint and fix the problem (a bad plugin, a theme function, a corrupted core file, etc.).
6. Important: Once the issue is resolved, set WP_DEBUG back to false on a live site to avoid exposing error details to visitors.

Checking the Server Error Log

Your hosting provider also keeps its own error log. In cPanel, go to Metrics > Errors to see the most recent server errors. Managed WordPress hosts such as WP Engine, Kinsta, and Flywheel expose error logs inside their own dashboards. These logs often contain the most direct explanation of the 500 error.

Fix 6: Re-upload WordPress Core Files

If none of the above steps work, your WordPress core files may have been corrupted — either during a failed update or as the result of a malware infection. Re-uploading fresh core files replaces any damaged files without touching your themes, plugins, or database.

Re-uploading Core Files via FTP

1. Download the latest version of WordPress from wordpress.org/download and extract the zip file on your computer.
2. Inside the extracted folder, delete the wp-content folder — you must not upload this, as it would overwrite your themes, plugins, and uploads.
3. Connect to your server via FTP.
4. Upload all remaining files and folders from the extracted WordPress folder to your server's root directory, choosing to overwrite existing files when prompted.
5. Reload your site. The freshly uploaded core files should resolve any corruption.

Re-uploading Core Files via WP-CLI

SSH users can accomplish the same thing in a single command:

wp core download --force

The --force flag overwrites existing core files while leaving wp-content and wp-config.php intact.

Frequently Asked Questions

Why does the WordPress 500 internal server error happen after an update?

Updates — whether to WordPress core, a plugin, or a theme — can introduce code that is incompatible with your PHP version, conflicts with another plugin, or exhausts your server's memory limit. Deactivating plugins and switching to a default theme after an update quickly identifies which component is responsible.

Can the 500 error be caused by my hosting provider?

Yes. Sometimes the problem originates entirely on the server side — for example, a misconfigured server module, a temporary resource limit being hit, or a server restart during a file operation. If you have tried all the fixes above and the error persists, contact your host's support team and ask them to check the server error logs for your account.

Will I lose my data if I re-upload WordPress core files?

No. Re-uploading core files only replaces files in the wp-admin and wp-includes folders and the root-level PHP files. Your wp-content folder (themes, plugins, uploads) and your database remain completely untouched, so no posts, pages, or media are lost.

How do I prevent the 500 internal server error from happening again?

Keep WordPress core, themes, and plugins updated. Test updates on a staging environment before applying them to your live site. Maintain regular backups using a plugin such as UpdraftPlus or your host's backup tool. Set an appropriate PHP memory limit proactively in wp-config.php, and audit your plugins regularly to remove any that are outdated or no longer maintained.

Fixing a 500 internal server error is usually straightforward once you work through the causes methodically — regenerating .htaccess, raising the memory limit, isolating a bad plugin or theme, and re-uploading core files cover the vast majority of cases. If you would rather not dig through FTP clients, configuration files, and error logs manually, WP AI Agent lets you diagnose and resolve issues like the WordPress 500 error simply by describing the problem in plain English through a natural-language AI chat interface, making complex WordPress troubleshooting accessible to everyone.