How to Fix 500 Internal Server Error in WordPress

The 500 Internal Server Error in WordPress is a common yet perplexing issue that webmasters face, signaling a general server-side error. Its ambiguity lies in the range of potential causes, from plugin conflicts to resource limitations. Addressing this error is crucial for maintaining the availability and functionality of your WordPress site. Quick and effective resolution ensures minimal disruption to your website’s visitors, safeguarding your site’s reputation and user experience.

Table of Common Causes and Solutions

What is a “500 Internal Server Error”?

The 500 Internal Server Error acts as a generic message indicating that something went wrong on the website’s server, but the server cannot pinpoint the specific issue. For WordPress site owners, this error can be particularly frustrating as it impedes access to the site, affecting both backend and frontend operations. Symptoms include a blank website page or a message directly stating there’s a “500 Internal Server Error”. Variations of this error message might appear differently depending on the browser, server, or specific situation, including phrases like “HTTP Error 500” or “Internal Server Error”. Recognizing these signs early can help in initiating a timely fix.

Pre-Troubleshooting Steps

Before diving into troubleshooting the 500 Internal Server Error, it’s imperative to secure your WordPress site with a complete backup. This precautionary step ensures that you can restore your site to its previous state should any changes exacerbate the issue or lead to data loss. Several reliable backup solutions and plugins facilitate this process, including:

• BackUpWordPress: A user-friendly plugin for automated site backups.
• VaultPress: Offers real-time backup and security scanning services.
• UpdraftPlus: Enables scheduled backups and easy restoration.

Implementing one of these solutions provides peace of mind as you proceed to diagnose and address the server error.

Common Causes and Solutions

1. Check Your .htaccess File

A corrupted .htaccess file is a frequent culprit behind the 500 Internal Server Error. This essential file, used for rewriting URLs, can become corrupted through plugin installations or manual edits gone awry. To diagnose and fix this issue:

• Identify a Corrupted File: Access your website via FTP or cPanel, navigate to the root directory where WordPress is installed, and look for the .htaccess file. A sudden appearance of the server error after changes to your site is a strong indicator of corruption.
• Create a New .htaccess File: Rename the existing .htaccess file to something like .htaccess_old to deactivate it. Then, in the WordPress admin area, go to Settings > Permalinks and simply click ‘Save Changes’ to generate a new .htaccess file. If you cannot access the WordPress dashboard, manually create a new file with the default WordPress .htaccess content:

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

Upload this file to your root directory. If your site returns to normal, the issue was indeed a corrupted .htaccess file.

2. Increase PHP Memory Limit

Exceeding your PHP memory limit can also trigger a 500 Internal Server Error. This limit can be reached due to poorly coded plugins or resource-intensive themes. To resolve this:

• Signs You’re Hitting Your Limit: Common indicators include the error occurring after installing a new plugin or theme, or during high-traffic periods.
• How to Increase the PHP Memory Limit:
• .htaccess Method: Access your site’s root directory via FTP or cPanel, find the .htaccess file, and add the following line: php_value memory_limit 256M. This increases your limit to 256MB.
• php.ini Method: If you have access to your php.ini file (usually found in the wp-admin directory), change the line memory_limit = 64M (or whatever the current limit is) to memory_limit = 256M to increase the limit.
• wp-config.php Method: Add define('WP_MEMORY_LIMIT', '256M'); to your wp-config.php file, just before the line that says /* That’s all, stop editing! Happy blogging. */. This code instructs WordPress to increase the PHP memory limit to 256MB.

Implementing these changes can help alleviate memory limit issues, potentially resolving the 500 Internal Server Error. Always ensure to refresh your website after applying each method to check if the issue has been resolved.

3. Audit Your Plugins

Plugins enhance functionality but can sometimes lead to a 500 Internal Server Error, especially if they’re outdated or conflict with other plugins. To identify and fix problematic plugins:

• Identifying Problematic Plugins: If the error appears after installing or updating a plugin, that plugin could be the cause. High resource consumption or compatibility issues with WordPress core or other plugins are common culprits.
• Steps to Deactivate and Isolate the Faulty Plugin: Access your site via FTP and navigate to the wp-content/plugins directory. Rename the plugins folder to something like plugins_old to deactivate all plugins. If your site works again, the issue is with one of the plugins. Rename the folder back to plugins and then rename each plugin folder inside it, one by one, until you find the culprit. After identifying the problematic plugin, you can choose to replace it, seek an update from the developer, or find an alternative plugin that offers similar functionality.

4. Check File Permissions

Correct file permissions are crucial for the security and functionality of your WordPress site. Incorrect permissions can lead to a 500 Internal Server Error. Here’s how to ensure your file permissions are set correctly:

• Correct File Permissions: Directories should be set to 755 or 750, and files should be set to 644 or 640. The wp-config.php file can be more restrictive, with permissions like 440 or 400 to prevent unauthorized access.
• How to Check and Modify File Permissions: Use an FTP client to access your server. Navigate to your WordPress root directory and right-click on files and directories to check their permissions. For directories, ensure the permission is set to 755 or 750. For files, ensure it’s set to 644 or 640. If you find permissions set to anything else, change them accordingly. This process can be tedious if done manually for each file, so you may use command-line tools if you have SSH access, or some FTP clients allow changing permissions for multiple files and directories simultaneously.

Adjusting file permissions to their correct settings can resolve the 500 Internal Server Error if it was caused by incorrect permissions, enhancing your site’s security and accessibility.

5. Reinstall WordPress Core Files

Occasionally, WordPress core files may become corrupted due to hacking, incorrect file editing, or updates gone wrong, leading to a 500 Internal Server Error. Reinstalling these files can often fix the issue without affecting your site’s content or design.

When and Why: If the error persists after checking .htaccess, increasing PHP memory limits, auditing plugins, and verifying file permissions, corrupted core files might be the cause. Reinstalling ensures you have a clean, error-free set of WordPress core files.

Step-by-Step Guide:

1. Backup Your Website: Always start with a full backup of your WordPress site.
2. Download WordPress: Get the latest version from the official WordPress.org site.
3. Unzip and Prepare: Unzip the downloaded file and delete the wp-content folder to avoid overwriting your themes, plugins, and uploads.
4. Upload via FTP: Use an FTP client to upload the remaining files to your WordPress root directory, overwriting the existing files. This process replaces the core files without affecting your content.

6. Contact Your Web Host

If you’ve exhausted all troubleshooting steps without resolving the 500 Internal Server Error, it’s time to contact your web hosting provider. They have access to server logs and deeper system insights that can pinpoint the issue.

• When to Reach Out: After attempting to fix the error through common solutions without success.
• Information to Provide: Share the steps you’ve already taken to resolve the error, any specific error messages you’ve encountered, and the exact time the error first occurred. This information can significantly speed up the support process.

Advanced Troubleshooting Techniques

For more complex scenarios where standard fixes don’t resolve the 500 Internal Server Error, consider these advanced troubleshooting techniques:

• Debugging Mode: Enable WordPress debugging by setting WP_DEBUG to true in your wp-config.php file. This can reveal specific PHP errors contributing to the server error.
• Server Logs: Request access to your server error logs from your hosting provider. These logs can offer detailed insights into what’s causing the error.
• Security Scans: Use security plugins like Wordfence or Sucuri to scan your site for malware or security breaches that could be causing the error.
• PHP Version: Ensure your PHP version is compatible with your WordPress version. Outdated PHP can cause various issues, including the 500 error.
• Database Repair: Corrupted databases can also lead to server errors. Use the WordPress database repair tool by adding define('WP_ALLOW_REPAIR', true); to your wp-config.php file and accessing yourwebsite.com/wp-admin/maint/repair.php.

Employing these advanced techniques can help uncover and fix less common causes of the 500 Internal Server Error, restoring your WordPress site to full functionality.

FAQs

In conclusion, the 500 Internal Server Error in WordPress can stem from a variety of sources, from simple .htaccess issues to more complex plugin conflicts or server limitations. By methodically troubleshooting—starting with the most common causes and working through to more advanced diagnostics—you can identify and resolve the issue. Remember, regular backups and timely updates are your best defense against potential disruptions, ensuring your WordPress site remains healthy and accessible to all users.