The 500 Internal Server Error is one of the most common yet frustrating issues WordPress users face. It offers no clear indication of what’s wrong and can bring your entire site to a halt. Whether you’re a developer, site owner, or freelancer, understanding how to quickly diagnose and fix this error is essential.
In this complete guide, we’ll walk through everything you need to know to identify and resolve the 500 error on your WordPress website.
What Is a 500 Internal Server Error?
A 500 Internal Server Error is a general HTTP status code that means something has gone wrong on the server, but the server can’t be more specific about the exact problem. It’s a server-side error, meaning the problem is not with your browser or internet connection but with your website’s server or application.
Common Symptoms
- A white screen with a generic “500 Internal Server Error” message
- Inability to access the admin dashboard (/wp-admin)
- Slow loading before showing the error
- Random page errors across the site
What Causes the 500 Internal Server Error in WordPress?
Several possible issues can trigger a 500 error. Here are the most common ones:
- Corrupted .htaccess file
- Plugin or theme conflict
- Exhausted PHP memory limit
- Corrupt core WordPress files
- Server configuration errors
- File permission issues
- PHP version incompatibility
- Errors in custom code
Step-by-Step Guide to Fix the 500 Internal Server Error
1. Back Up Your Website First
Before making any changes, back up your website. If you have access to your admin area, use a backup plugin like UpdraftPlus. Otherwise, use cPanel or FTP to download your files and database.
2. Check the .htaccess File
The .htaccess file controls how Apache servers handle URLs and redirects. A corrupted .htaccess file is a common cause of 500 errors.
How to Fix:
- Connect to your site using FTP or File Manager in cPanel.
- Locate the .htaccess file in the root directory.
- Rename it to .htaccess_backup.
- Try reloading your site.
If it works, log in to your WordPress dashboard, go to Settings > Permalinks, and click Save Changes to regenerate a new .htaccess file.
3. Increase the PHP Memory Limit
WordPress needs a certain amount of memory to run. If it exceeds the allocated limit, it can trigger a 500 error.
How to Increase:
- Edit the wp-config.php file.
Add this line before the /* That’s all, stop editing! */ comment:
php
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define(‘WP_MEMORY_LIMIT’, ‘256M’);
- Save the file and refresh your site.
4. Deactivate All Plugins
A faulty plugin or a conflict between plugins can cause the server to fail.
Steps to Deactivate Plugins via FTP:
- Connect via FTP or File Manager.
- Navigate to wp-content/.
- Rename the plugins folder to plugins_old.
- Check your website.
If it loads, a plugin is the culprit. Rename the folder back to plugins, then rename individual plugin folders one at a time to isolate the problematic one.
5. Switch to a Default Theme
Themes can also cause compatibility or coding issues.
Steps to Switch Themes via FTP:
- Go to wp-content/themes/
- Rename your active theme folder (e.g., astra to astra_old)
- WordPress will default to a fallback theme like twentytwentyfour.
If the site works, the issue lies with your theme.
6. Check Error Logs
Server logs can provide clues about what’s causing the 500 error.
How to Access Logs:
- Log into cPanel and find Errors or Logs.
- Check the most recent entries for your site.
Alternatively, enable debugging in WordPress by adding the following to wp-config.php:
php
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define(‘WP_DEBUG’, true);
define(‘WP_DEBUG_LOG’, true);
define(‘WP_DEBUG_DISPLAY’, false);
This creates a debug.log file in wp-content.
7. Reinstall WordPress Core Files
Corrupted core files during an update or upload can break your site.
How to Reinstall:
- Download a fresh copy of WordPress from wordpress.org.
- Extract the files and delete the wp-content folder.
- Upload the remaining files via FTP, replacing the existing files.
This won’t affect your content but will refresh the core files.
8. Check File Permissions
Incorrect file and folder permissions can cause server errors.
Recommended Permissions:
- Folders: 755
- Files: 644
Use an FTP client or hosting file manager to update these permissions.
9. Check PHP Version Compatibility
Some plugins or themes may require a specific PHP version.
How to Check and Change:
- Log into cPanel.
- Go to Select PHP Version or MultiPHP Manager.
- Switch to a supported version like PHP 8.0 or 8.1.
10. Contact Your Hosting Provider
If none of the above fixes work, reach out to your hosting support. They can check server logs, resource limits, and security restrictions that might be causing the issue.
How to Prevent Future 500 Errors
- Keep WordPress core, plugins, and themes updated
- Use quality, well-coded themes and plugins
- Regularly back up your site
- Monitor server resource usage
- Use staging environments for updates and custom code
- Enable logging to catch issues early
Final Thoughts
A 500 Internal Server Error can be alarming, but it’s usually fixable with a systematic approach. By following the steps in this guide, you can quickly identify the cause and restore your site’s functionality.
If you’re not comfortable dealing with server-side issues, consider using a professional WordPress support service to resolve the problem safely and efficiently.