Troubleshooting “An Unexpected Error Occurred” in WordPress

WordPress is one of the most popular content management systems in the world, powering millions of websites. Despite its reliability, users occasionally encounter the vague and frustrating message: “An unexpected error occurred. Something may be wrong with WordPress.” This error can appear during plugin updates, theme changes, or even normal site usage, leaving site owners unsure of what to do. Understanding the root causes and applying systematic troubleshooting can help restore your site quickly. In this guide, we explore common reasons behind this error and provide actionable solutions.

1. Enable WordPress Debugging

When WordPress shows a generic error, it often hides the underlying problem, which could be caused by PHP issues, database errors, or plugin conflicts. Enabling debugging allows you to see the exact error details.

Steps to enable debugging:

  1. Access your website files using FTP or your hosting file manager.

  2. Open the wp-config.php file located in the root directory of your WordPress installation.

  3. Add or update the following lines:


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

  1. Save the file and reload your site. All errors will now be logged in wp-content/debug.log.

By checking this log, you can pinpoint whether the error is caused by a plugin, theme, or server-side issue. This step is crucial because it eliminates guesswork and gives you concrete information to act on.

2. Check for Plugin or Theme Conflicts

Most unexpected errors in WordPress are due to conflicts between plugins or between a plugin and the theme. These conflicts can occur after updates or when incompatible plugins are installed.

How to troubleshoot plugin conflicts:

  • Deactivate all plugins at once. If you cannot access the admin dashboard, rename the wp-content/plugins folder via FTP to something like plugins_old.

  • Reload your website. If the site works, reactivate plugins one by one to identify the culprit.

How to troubleshoot theme conflicts:

  • Temporarily switch to a default WordPress theme such as Twenty Twenty-Three.

  • If the error disappears, your original theme likely has a compatibility issue or a coding error.

This process can be time-consuming, but it is one of the most reliable ways to identify the exact source of the problem.

3. Check PHP Version Compatibility

WordPress and its plugins rely heavily on PHP. Using an outdated or unsupported PHP version can trigger unexpected errors. Many modern themes and plugins require PHP 7.4 or higher.

Steps to check and update PHP:

  • Access your hosting control panel or cPanel.

  • Look for PHP settings to see the current version.

  • Update to PHP 8.0–8.2 if possible, as these versions are optimized for performance and security.

Using a compatible PHP version ensures that all WordPress functions work correctly and prevents compatibility-related errors.

4. Increase PHP Memory Limit

Sometimes WordPress errors occur because the server does not allocate enough memory for PHP processes. Low memory can result in fatal errors, especially on sites with multiple plugins or heavy themes.

Steps to increase memory limit:

  1. Edit your wp-config.php file.

  2. Add this line:


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

  1. Save the file and refresh your website.

Increasing the memory limit allows WordPress to execute more complex tasks, reducing the chances of encountering fatal errors.

5. Verify File Permissions

Incorrect file or folder permissions can prevent WordPress from accessing necessary files, resulting in unexpected errors. Permissions define who can read, write, or execute files on the server.

Recommended permissions:

  • Folders: 755

  • Files: 644

Using FTP or your hosting file manager, ensure that these permissions are set correctly. Adjusting permissions can solve errors related to file access and updates.

6. Review Recent Updates or Changes

WordPress errors often appear immediately after updating plugins, themes, or the WordPress core. Sometimes, updates introduce conflicts, or corrupted files may cause issues.

Tips for handling recent changes:

  • Roll back updates if possible using a backup.

  • Reinstall plugins or themes to ensure no files are missing.

  • Always create regular backups before updating WordPress components to minimize downtime and recovery time.

Monitoring updates carefully helps prevent unexpected errors in the future.

7. Check Server Logs and Contact Hosting Support

If the above steps do not resolve the issue, the problem may be server-related. Hosting environments can have misconfigurations, outdated software, or database issues that cause WordPress to fail.

Steps to investigate:

  • Check server error logs via your hosting control panel.
  • Contact hosting support with details from your WordPress debug log.

Professional hosting support can identify problems like database connection errors, permission restrictions, or server-level conflicts that may not be apparent from WordPress alone.

Top Actionable Fixes for “An Unexpected Error Occurred” in WordPress

Enable WordPress Debugging to Identify the Exact Issue
Turn on debugging in WordPress to reveal the specific PHP or database error. Edit your wp-config.php file and add:


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

Check the wp-content/debug.log file to pinpoint the exact cause of the error.

Deactivate All Plugins and Reactivate One by One
Plugin conflicts are the most common cause of this error. Deactivate all plugins via the dashboard or by renaming the wp-content/plugins folder via FTP. Then, reactivate each plugin individually to find the one causing the issue.

Switch to a Default WordPress Theme
Themes can sometimes conflict with WordPress or plugins. Temporarily switch to a default theme like Twenty Twenty-Three. If the error disappears, your original theme may be incompatible or have a coding issue.

Check and Update Your PHP Version
Running outdated PHP can cause unexpected WordPress errors. Ensure your server uses PHP 8.0–8.2 for better performance, security, and compatibility with the latest WordPress core, themes, and plugins.

Increase PHP Memory Limit in WordPress
Low memory allocation can trigger fatal errors. Add the following line to your wp-config.php to increase the limit:


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

This allows WordPress to handle more plugins, scripts, and database queries without crashing.

Verify and Correct File Permissions
Incorrect file permissions can prevent WordPress from accessing necessary files. Use FTP or your hosting panel to set folders to 755 and files to 644. This ensures WordPress can read, write, and execute files properly.

Rollback Recent Updates or Restore a Backup
If the error appeared after a WordPress, plugin, or theme update, rolling back to the previous version can resolve it. Always keep regular backups to restore your site quickly in case of conflicts.

Check Server Logs and Contact Hosting Support
If none of the above fixes work, the issue may be server-related. Hosting support can review server error logs, database settings, and PHP configurations to identify the problem.

Use a Staging Site for Testing Updates
To prevent future errors, test WordPress core, plugin, and theme updates on a staging site before applying them to your live site. This allows you to catch conflicts and fix issues without affecting your live website.

Regularly Maintain and Monitor Your WordPress Site
Keep your WordPress, plugins, themes, and server environment updated. Perform regular backups, monitor memory usage, and review server logs periodically. Proactive maintenance reduces the likelihood of unexpected errors and ensures your site runs smoothly.

Frequently Asked Questions (FAQs)

What are the main causes of the “An unexpected error occurred” message in WordPress websites?
This common WordPress error message can appear for several reasons, including plugin conflicts, theme incompatibilities, outdated PHP versions, insufficient server memory, corrupted WordPress core files, or database connection issues. It can occur during plugin updates, theme changes, WordPress core upgrades, or even while performing routine website tasks. Identifying the root cause often requires enabling WordPress debugging or checking server error logs to see the exact PHP or database error behind the message.

How can I find out the exact cause of the unexpected error in WordPress?
WordPress hides detailed error messages by default to protect your site. To identify the exact problem, you can enable debugging by editing your wp-config.php file and adding the following lines:


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

This logs all PHP errors, warnings, and notices to wp-content/debug.log. Checking this file provides detailed insights into whether the issue is caused by a plugin, theme, database error, or server configuration, helping you take targeted action.

Can WordPress plugins cause the “An unexpected error occurred” problem?
Yes, plugins are one of the most frequent causes of this WordPress error. Incompatible, outdated, or poorly coded plugins can conflict with other plugins or your active theme, triggering the error. To troubleshoot, deactivate all plugins and reactivate them one by one to identify the problematic plugin. Regularly updating plugins and using trusted, high-quality sources reduces the risk of plugin-related errors.

Could a WordPress theme trigger the unexpected error message?
Absolutely. A WordPress theme contains PHP, CSS, and JavaScript code that can sometimes conflict with core WordPress functionality or plugins. Themes that are outdated or poorly coded are more likely to cause errors. Temporarily switching to a default WordPress theme, such as Twenty Twenty-Three, can help determine whether your active theme is responsible. If the error disappears, you may need to update the theme or contact the developer for support.

Does the PHP version of my hosting server affect WordPress errors?
Yes, using an outdated or incompatible PHP version can cause unexpected errors in WordPress. Many modern themes and plugins require PHP 7.4 or higher to function correctly. Running an older version of PHP may lead to fatal errors or deprecated function issues. It is recommended to use PHP versions 8.0–8.2 for optimal performance, security, and compatibility with the latest WordPress updates.

How do insufficient server memory and PHP memory limits cause WordPress errors?
WordPress requires enough server memory to execute scripts, load plugins, and handle complex database queries. If the server allocates too little memory, it may trigger fatal errors, especially on sites with many plugins or large databases. Increasing the PHP memory limit in wp-config.php with:


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

can resolve memory-related errors and prevent the “An unexpected error occurred” message.

Can incorrect file permissions in WordPress cause unexpected errors?
Yes, improper file or folder permissions can prevent WordPress from accessing essential files, updating plugins, or writing cache data. Recommended permissions are 755 for folders and 644 for files. Using FTP or your hosting control panel to verify and adjust file permissions ensures WordPress can read, write, and execute files properly, reducing the likelihood of errors.

Can recent WordPress updates trigger the “An unexpected error occurred” problem?
Yes, WordPress core, theme, or plugin updates can sometimes introduce conflicts or errors, especially if a plugin or theme is incompatible with the new version. Rolling back updates, reinstalling the updated plugin/theme, or restoring a backup often resolves the issue. Testing updates on a staging site before applying them to your live website can prevent these errors from occurring.

What should I do if I cannot fix the WordPress unexpected error myself?
If debugging, plugin/theme troubleshooting, and server checks do not resolve the issue, the problem may lie deeper in the server environment. Hosting providers can check server logs, database integrity, PHP configurations, and other server-level issues. Providing your debug log to hosting support helps them identify and resolve the error efficiently.

How can I prevent the “An unexpected error occurred” message in WordPress in the future?
Preventive measures include keeping WordPress, themes, and plugins updated, using high-quality and well-supported plugins/themes, performing regular backups, monitoring server performance, and ensuring PHP versions are compatible. Testing updates on a staging environment before applying them to the live site also reduces the risk of encountering unexpected errors.

Encountering the “An unexpected error occurred” message in WordPress can be stressful, but in most cases, it is fixable with systematic troubleshooting. By enabling debugging, checking plugins and themes, verifying PHP versions, increasing memory limits, and reviewing file permissions, you can usually identify and resolve the issue quickly. Regular site maintenance, timely updates, and using a staging environment for testing changes can prevent such errors from occurring in the future. For users who want a professional solution without spending hours troubleshooting, the WPCodex Team is highly recommended. With their expertise in WordPress core, plugin conflicts, theme compatibility, and server configurations, they can efficiently resolve unexpected errors and ensure your website remains secure, stable, and fully functional. Partnering with a trusted team like WPCodex guarantees peace of mind and expert support whenever WordPress issues arise.