How to Fix “There Has Been a Critical Error” in WordPress

Seeing the message “There has been a critical error on this website” can be alarming, especially if it appears on your live WordPress site without warning. The good news is that this error usually doesn’t mean your website is permanently broken. In most cases, it’s triggered by a problem that can be identified and fixed with the right troubleshooting steps.

A WordPress critical error typically occurs when a plugin conflict, theme issue, PHP error, insufficient memory limit, corrupted core files, or a failed update prevents WordPress from loading correctly. To protect your site and its visitors, WordPress hides the underlying PHP error and displays this generic message instead.

In many cases, this error prevents your website from loading altogether. If your site is displaying a blank page, loading indefinitely, or returning a generic error, our guide on why your WordPress site is not loading can help you identify other possible causes.

In this guide, you’ll learn how to diagnose the root cause of the error and fix it using proven methods, starting with the simplest solutions like Recovery Mode and progressing to more advanced troubleshooting techniques if needed. Whether you still have access to your WordPress dashboard or your site is completely inaccessible, these steps will help you get your website back online quickly.

What Causes This WordPress Error?

The “There has been a critical error on this website” message appears when WordPress encounters a fatal PHP error that prevents it from loading properly. Instead of displaying technical error details to visitors, WordPress shows this generic message to protect sensitive information and improve security.

Several issues can trigger a critical error, but the most common causes include:

Plugin Conflicts

Plugins are the most frequent cause of WordPress critical errors. A recently installed or updated plugin may conflict with another plugin, your active theme, or your current PHP version. Since plugins execute code every time your website loads, even a single incompatible plugin can cause your entire site to become inaccessible.

Theme Conflicts

An outdated, poorly coded, or incompatible theme can also trigger a critical error. This often happens after updating WordPress, switching themes, or adding custom code to files like functions.php. If your theme contains invalid PHP code, WordPress may fail to load altogether.

PHP Errors

WordPress is built on PHP, so any fatal PHP error can stop your website from functioning. Common examples include syntax errors, undefined functions, missing classes, or incompatibility with newer PHP versions. These errors are typically recorded in your site’s debug log, making them easier to identify during troubleshooting.

Insufficient PHP Memory Limit

Every WordPress website is allocated a certain amount of PHP memory by the server. If a plugin, theme, or script requires more memory than is available, WordPress may crash and display a critical error. This is especially common on resource-intensive websites or shared hosting environments with lower memory limits.

Corrupted WordPress Core Files

Interrupted updates, accidental file deletions, malware infections, or server issues can corrupt essential WordPress core files. When critical files are missing or damaged, WordPress may be unable to initialize correctly, resulting in the error message.

Fortunately, most of these issues can be resolved without rebuilding your website. In the following sections, we’ll walk through the most effective solutions, starting with the simplest fixes and progressing to more advanced troubleshooting methods.

How to Fix the Critical Error in WordPress

The best way to troubleshoot a WordPress critical error is to start with the simplest and least invasive solution. Many issues can be resolved in just a few minutes without affecting your website’s content or settings. If one method doesn’t work, simply move on to the next until you identify the root cause.

1. Use WordPress Recovery Mode

If the critical error was caused by a plugin or theme, WordPress may automatically send a Recovery Mode email to your site administrator. This email contains a unique link that lets you log into your dashboard, even if your website is otherwise inaccessible.

Once you’re in Recovery Mode, WordPress will identify the plugin or theme responsible for the error. You can then deactivate the faulty plugin or switch themes without affecting the rest of your website.

To use Recovery Mode:

1. Check your administrator email inbox for a message from WordPress.
2. Click the Recovery Mode link provided in the email.
3. Log in to your WordPress dashboard.
4. Follow the on-screen instructions to disable the problematic plugin or theme.
5. Visit your website again to verify that the issue has been resolved.

Tip: If you didn’t receive the Recovery Mode email, don’t worry. You can still troubleshoot the issue using the methods below.

2. Enable Debug Mode

If Recovery Mode isn’t available, the next step is to identify what’s causing the error. WordPress includes a built-in debugging feature called WP_DEBUG that records PHP errors in a log file.

To enable Debug Mode:

1. Access your website using FTP or your hosting provider’s File Manager.
2. Open the wp-config.php file located in your WordPress root directory.
3. Find the following line:

define( ‘WP_DEBUG’, false );

4. Replace it with:

define( ‘WP_DEBUG’, true );

define( ‘WP_DEBUG_LOG’, true );

define( ‘WP_DEBUG_DISPLAY’, false );

5. Save the file and reload your website.
6. Open the wp-content/debug.log file to review any recorded errors.

The log often points directly to the plugin, theme, or file responsible for the issue, making it much easier to resolve.

3. Disable Plugins

Plugin conflicts are one of the most common causes of WordPress critical errors, especially after installing a new plugin or performing an update.

If the error appeared immediately after updating a plugin, there’s a good chance the update introduced a compatibility issue. Follow this guide first, then check our detailed article on fixing a WordPress website that broke after a plugin update for more targeted troubleshooting. 

If you can access the WordPress dashboard:

1. Go to Plugins > Installed Plugins.
2. Deactivate recently installed or updated plugins.
3. Refresh your website to see if the error disappears.

If you cannot access the dashboard:

1. Connect to your website using FTP or your hosting provider’s File Manager.
2. Navigate to:

wp-content/plugins

3. Rename the plugins folder to something like plugins-disabled.
4. Refresh your website.

Renaming the folder temporarily disables all plugins. If your website starts working again, rename the folder back and reactivate plugins one at a time until you identify the problematic one.

4. Switch to a Default Theme

If disabling plugins doesn’t fix the problem, your active theme could be responsible.

If the critical error only occurs while editing pages with Elementor, the issue may be specific to the page builder rather than WordPress itself. In that case, see our guide on fixing the Elementor editor not loading.

To test this:

1. Open the wp-content/themes directory.
2. Rename your active theme folder.
3. If a default WordPress theme such as Twenty Twenty-Five is installed, WordPress will automatically activate it.

If your website loads successfully after switching themes, the issue is likely caused by your previous theme or recent theme customizations.

5. Increase the PHP Memory Limit

Some plugins and themes require more server memory than your hosting plan currently allows. When WordPress exceeds the available PHP memory, it may trigger a critical error.

Low PHP memory limits can also affect your website’s overall performance. If your site is loading but responding slowly, you may also want to read our guide on why WordPress websites become slow.

You can increase the memory limit by editing your wp-config.php file and adding the following line above the “That’s all, stop editing!” comment:

define( ‘WP_MEMORY_LIMIT’, ‘256M’ );

Save the file and reload your website.

If the memory limit doesn’t increase, your hosting provider may enforce a server-level restriction. In that case, you’ll need to contact your host and request a higher PHP memory limit.

6. Reinstall WordPress Core Files

Corrupted or incomplete WordPress core files can prevent your website from loading properly.

To reinstall WordPress safely:

1. Download the latest version of WordPress from the official website.
2. Extract the ZIP file.
3. Upload all files except the wp-content folder and the wp-config.php file.
4. Allow the new files to overwrite the existing core files.

This replaces damaged WordPress files without affecting your themes, plugins, uploads, or database.

7. Check Your PHP Version

An outdated or unsupported PHP version can cause plugins and themes to fail, especially after major WordPress updates.

To check your PHP version:

1. Log in to your hosting control panel.
2. Open the PHP management section.
3. Verify that your website is running a PHP version supported by your current WordPress installation and plugins.

If you’ve recently upgraded PHP and the error appeared afterward, temporarily switching back to the previous version can help confirm whether compatibility is the issue.

Before upgrading or downgrading PHP, always ensure your themes and plugins support the selected version.

8. Restore a Backup (Last Resort)

If none of the previous methods resolve the problem, restoring a recent backup is often the fastest way to get your website back online.

Restore a backup only if:

• The error appeared after a major update or migration.
• You cannot determine the cause of the issue.
• You have a recent backup taken before the problem occurred.

Most hosting providers and backup plugins allow you to restore your website with just a few clicks.

Keep in mind that any changes made after the backup was created may be lost, so use this option only after exhausting the other troubleshooting methods.

Pro Tip: Once your website is working again, update your plugins, themes, and WordPress core one at a time. Testing each change individually makes it much easier to identify the exact cause if the error returns.

How to Prevent WordPress Critical Error

While most WordPress critical errors can be fixed, preventing them in the first place can save you time, stress, and potential downtime. Following a few best practices can significantly reduce the chances of encountering this issue again.

Update Plugins and Themes Carefully

Outdated software can introduce security vulnerabilities, but updating everything at once can also lead to compatibility issues. Before updating, review the plugin or theme’s changelog, verify that it’s compatible with your current WordPress and PHP versions, and update one item at a time. This makes it much easier to identify the source of a problem if an error occurs.

Test Changes on a Staging Site

Avoid making major changes directly on your live website. Whether you’re installing a new plugin, switching themes, or upgrading WordPress, test everything on a staging site first. A staging environment allows you to identify compatibility issues without affecting your visitors or risking downtime.

Keep Regular Backups

A recent backup is your best safety net if something goes wrong. Schedule automatic backups of both your website files and database, and store copies in a secure off-site location such as cloud storage. If a critical error occurs after an update or configuration change, you can quickly restore your website to a working state.

Use a Compatible PHP Version

Running an outdated or unsupported PHP version can cause plugins and themes to malfunction. Likewise, upgrading to a newer PHP version before your plugins are compatible can also trigger errors. Regularly check your hosting account to ensure you’re using a PHP version recommended by WordPress and supported by all your installed themes and plugins.

By following these simple practices, you can minimize the risk of future critical errors and keep your WordPress website running smoothly. Even if an issue does arise, having backups, a staging site, and a well-maintained environment will make recovery much faster and less stressful.

Frequently Asked Questions

Conclusion

The “There has been a critical error on this website” message may seem intimidating, but it’s usually caused by a plugin conflict, theme issue, PHP error, or corrupted WordPress file that can be resolved with the right troubleshooting steps.

Start with the simplest solutions first, such as WordPress Recovery Mode, Debug Mode, and disabling plugins, before moving on to more advanced fixes like reinstalling WordPress core files, checking your PHP version, or restoring a backup. Taking a step-by-step approach makes it easier to identify the root cause without making unnecessary changes to your website.

Once your site is back online, take preventive measures like keeping regular backups, testing updates on a staging site, and ensuring your plugins, themes, and PHP version remain compatible. These best practices can help reduce the risk of future critical errors and keep your WordPress website running smoothly.