WordPress

How to Fix 500 Internal Server Error in WordPress

A 500 Internal Server Error error in WordPress is usually caused by one of a handful of configuration problems. Work through the causes below in order - the first ones are the most common.

Common Causes in WordPress

• Corrupted .htaccess file
• PHP memory limit exhausted
• Plugin conflict or error
• Theme compatibility issue
• Corrupted WordPress core files
• Database connection error

Step-by-Step Solutions

Solution 1: Regenerate .htaccess File

1. Rename existing .htaccess to .htaccess.old via FTP
2. Go to WordPress Admin → Settings → Permalinks
3. Click Save Changes without making any changes
4. WordPress will generate a new .htaccess file
5. Test if error is resolved

Solution 2: Increase PHP Memory Limit

1. Edit wp-config.php file
2. Add this line before /* That's all, stop editing! */: define('WP_MEMORY_LIMIT', '256M');
3. Save and upload the file
4. Alternatively, edit php.ini: memory_limit = 256M

Solution 3: Deactivate All Plugins

1. Via FTP, rename /wp-content/plugins/ to /wp-content/plugins-old/
2. Check if site works - this deactivates all plugins
3. Rename back to plugins/
4. Rename plugin folders one by one to identify the problematic plugin
5. Delete or replace the faulty plugin

Solution 4: Switch to Default Theme

1. Via FTP, rename /wp-content/themes/your-theme/ to /wp-content/themes/your-theme-old/
2. WordPress falls back to an installed default theme (e.g. Twenty Twenty-Four) if one is present
3. If this fixes it, your theme has an error
4. Contact theme developer or restore from backup

Solution 5: Enable WordPress Debug Mode

1. Edit wp-config.php
2. Change define('WP_DEBUG', false); to define('WP_DEBUG', true);
3. Add define('WP_DEBUG_LOG', true);
4. Add define('WP_DEBUG_DISPLAY', false);
5. Check /wp-content/debug.log for error details

Prevention Tips

• Watch the WordPress error logs and alert on rising error rates
• Test configuration changes in a staging environment first
• Keep configuration under version control so you can roll back quickly
• Run a configuration test (e.g. nginx -t or apachectl configtest) before every reload