How to Fix “There Has Been a Critical Error on This Website” in WordPress (Step-by-Step Guide)
WordPress powers a massive portion of the web because of its flexibility, scalability, and ease of use. But even the most well-built websites can occasionally break. One of the most alarming errors users encounter is:
“There has been a critical error on this website.”
At first glance, it sounds serious and overwhelming. In reality, this is a common issue and in most cases, it can be fixed without advanced technical knowledge.
This guide will walk you through exactly why this error happens, how to identify the root cause, and how to fix it step by step so your website is back online quickly.
If your website is down and affecting your business, consider using a professional WordPress maintenance service to resolve issues quickly.
What Causes This Critical Error?
This error is usually triggered by a fatal PHP issue. Instead of showing detailed errors publicly, WordPress hides them and displays this generic message for security reasons.
Here are the most common causes:
1. Plugin Conflicts or Failures
Plugins are the number one culprit. A poorly coded or outdated plugin can break your entire site, especially after updates.
2. Theme Compatibility Issues
Themes that are not updated or incompatible with your current WordPress version can trigger fatal errors.
3. Corrupted Core Files
If essential WordPress files are missing or modified incorrectly, your site may fail to load.
4. PHP Memory Limit Exhaustion
When your website exceeds its allocated memory, especially during high traffic or heavy plugin usage, it crashes.
5. Incorrect File Permissions
If your server cannot access files due to wrong permissions, WordPress cannot function properly.
6. Custom Code Errors
Any manual code changes in theme files, functions.php, or plugins can instantly break the site if not written correctly.
Step-by-Step Fix (Follow in Order)
Step 1: Check Your Email (Recovery Mode Link)
WordPress often sends an automated email to the admin when a critical error occurs.
This email includes:
- The exact cause of the error
- A Recovery Mode link
Click the link and log in. From there, you can safely disable the problematic plugin or theme.
This is the fastest and safest way to fix the issue.
Step 2: Enable Debug Mode to See the Exact Error
If you did not receive an email, enable debugging.
Access your site via FTP or File Manager and open:
wp-config.php
Find this line:
define('WP_DEBUG', false);
Change it to:
define('WP_DEBUG', true);
define('WP_DEBUG_LOG', true);
define('WP_DEBUG_DISPLAY', true);
Reload your website. You will now see the actual error message, which tells you exactly what is broken.
Step 3: Always Take a Full Backup First
Before making any fixes, take a complete backup of:
- Files
- Database
This ensures you can restore your site if something goes wrong.
Step 4: Disable All Plugins
If the issue is plugin-related, your site may not load the admin panel.
Use FTP:
- Go to /wp-content/
- Rename the folder plugins to plugins_old
This will deactivate all plugins instantly.
Now reload your site:
- If it works, the issue is confirmed to be a plugin
Rename the folder back and activate plugins one by one to find the faulty one.
Step 5: Switch to a Default Theme
If plugins are not the issue, your theme might be causing the crash.
Using FTP:
- Go to /wp-content/themes/
- Rename your active theme folder
WordPress will automatically switch to a default theme like Twenty Twenty-Four.
If your site starts working, your theme is the problem. Update or replace it.
Step 6: Increase PHP Memory Limit
Low memory is a silent killer in WordPress.
Edit wp-config.php and add:
define('WP_MEMORY_LIMIT', '256M');
This gives your site more resources to function properly.
Step 7: Fix File Permissions
Incorrect permissions can block access to critical files.
Use FTP and set:
- Folders: 755
- Files: 644
Also ensure wp-config.php is not overly restricted.
Step 8: Reinstall WordPress Core Files
If core files are corrupted:
- Download fresh WordPress from wordpress.org
- Replace wp-admin and wp-includes folders
- Do NOT overwrite wp-content
This restores your core system without affecting content.
Step 9: Check PHP Version Compatibility
Sometimes your server’s PHP version causes the issue.
Ensure your hosting supports:
- PHP 7.4 or higher (preferably PHP 8+)
Switch versions via your hosting panel and test.
If you are not comfortable making these changes, our team can help fix the issue safely without downtime.
How to Prevent This Error in the Future
Fixing is one part. Preventing is where real control comes in.
Keep Everything Updated
Regularly update:
- WordPress core
- Plugins
- Themes
Avoid Too Many Plugins
More plugins increase conflict risk. Use only what is necessary.
Use Quality Themes and Plugins
Stick to trusted developers and avoid nulled or poorly coded resources.
Set Up Automatic Backups
Use daily backups so you can restore instantly.
Use Staging Before Updates
Test major changes on a staging site before applying them live.
Monitor Website Health
Use uptime monitoring tools to detect issues early.
Final Thoughts
This error may look intimidating, but in most cases, it’s caused by something simple like a plugin conflict or theme issue.
The key is to stay calm and follow a structured approach:
- Identify the issue
- Isolate the cause
- Fix systematically
For business websites, downtime directly impacts leads, trust, and revenue. That is why having a reliable maintenance and monitoring process is just as important as building the website itself. For businesses that rely on their website for leads, having expert support makes all the difference. Explore how Arkido can help keep your website stable and growth-ready.
Once you understand how this error works, you will not only fix it faster but also prevent it from happening again.