Why is my WordPress website showing a critical error?

If your website displays the message “There has been a critical error on this website”, WordPress has encountered a problem that prevents part of the website from working correctly.

The error can affect:

• the entire website
• only the WordPress dashboard
• a specific page
• the checkout or another important function
• an action such as publishing, editing or submitting a form

The message can look alarming, especially when the website is part of your business. However, it does not necessarily mean that your content or data has been lost.

In many cases, the problem can be traced back to a plugin, theme, update or hosting configuration. The important thing is to avoid making several changes at once without knowing what caused the error.

This guide explains what you can check safely, what information you should collect and when it is better to ask for technical support.

What does a WordPress critical error mean?

A WordPress website is made up of different components that work together:

• WordPress itself
• plugins
• the active theme
• custom code
• the database
• the hosting environment

A critical error appears when one of these components encounters a problem serious enough to interrupt the normal loading of the page.

WordPress displays a generic message instead of showing visitors the full technical error. This is useful for security, but it also means that the message alone does not tell you what caused the problem.

A developer will normally need to inspect the website logs or identify which recent change triggered the error.

What may have caused the error?

The most common causes include:

A plugin was updated or activated

A plugin may not be compatible with:

• the current version of WordPress
• another active plugin
• the website theme
• the PHP version used by the hosting server
• custom functionality already present on the website

The plugin itself may not necessarily be poorly developed. Sometimes two perfectly valid tools simply interact in an unexpected way.

WordPress or the theme was updated

An update can reveal an existing compatibility issue or interrupt custom functionality that depends on an older version of the theme, plugin or platform.

The hosting environment changed

The problem may appear after:

• a change to the PHP version
• a server configuration update
• a migration
• a restore
• a change in permissions or available resources

These changes may be performed manually, automatically or directly by the hosting provider.

Custom code stopped working

The website may include custom functions created specifically for your business. An update to WordPress, a plugin or PHP can make older code incompatible.

An update was interrupted

If an update stops before all files are installed correctly, the website may be left with missing or inconsistent files.

The website ran out of available resources

A complex task, plugin conflict, import or background process may use more server memory than is available.

Increasing the available memory is not always the real solution. It is still necessary to understand why the website used so many resources.

First, try to understand what changed

You do not need to be a developer to collect useful information.

Think about what happened immediately before the error appeared.

For example:

• Did you update WordPress?
• Did you update, install or activate a plugin?
• Did you change the theme?
• Did someone edit the website?
• Was the website migrated?
• Was a backup restored?
• Did the hosting provider make any changes?
• Did the error appear while you were publishing, placing an order or editing a page?

Write down everything you remember, even if it does not seem technically important.

A simple note such as “the error appeared immediately after updating the payment plugin” can save a significant amount of diagnostic time.

Check whether the problem affects the whole website

Open the website in a private or incognito browser window and check:

• the homepage
• an internal page
• the login page
• the WordPress dashboard
• any important business function, such as checkout, forms or subscriptions

You may discover that the website is not completely offline.

For example:

• the public pages may work, but the dashboard may not
• only the checkout may be affected
• the error may appear on one specific page
• administrators may see the error while normal visitors do not

Knowing exactly where the error appears helps identify which part of the website is involved.

Check your WordPress administrator email

WordPress may send an email to the administrator address when it detects certain critical errors.

Check:

• the administrator inbox
• spam and junk folders
• any shared email address used to manage the website

The email may mention the plugin or theme involved. In some cases, it may also contain a link to WordPress Recovery Mode.

Recovery Mode can allow an administrator to access the dashboard while WordPress temporarily pauses the component that caused the problem.

Treat this link as sensitive information and do not share it publicly.

If you receive the email but do not understand what it means, you can forward the relevant information to D4Hub. Avoid sending passwords or access credentials by ordinary email.

What can you safely try?

The safest approach depends on how important the website is and how comfortable you are managing WordPress.

Option 1: contact the person who made the last change

If an agency, developer, colleague or hosting provider recently worked on the website, contact them first.

Ask whether they:

• installed or updated anything
• changed the PHP version
• deployed custom code
• restored a backup
• modified the server configuration

This is often the quickest way to understand what happened.

Option 2: contact your hosting provider

Your hosting provider may be able to tell you whether:

• a server error was recorded
• the PHP version changed
• the website exceeded available resources
• a recent backup is available
• the problem is related to the hosting environment

Hosting support may help identify the category of the problem. However, they may not be able to repair a plugin conflict, theme issue or custom WordPress code.

Option 3: deactivate a plugin from the dashboard

Only try this if you can still access WordPress and have a strong reason to suspect a specific plugin.

For example, the error may have appeared immediately after that plugin was updated.

Go to:

Plugins → Installed Plugins

Then deactivate the suspected plugin and check whether the affected page starts working again.

Do not deactivate several plugins at once unless you understand the consequences. Plugins may control:

• forms
• payments
• subscriptions
• security
• multilingual content
• backups
• caching
• analytics

A website that loads again is not necessarily fully operational.

After deactivating a plugin, test the important functions of the website.

Option 4: restore a backup

A restore may be appropriate when the website stopped working immediately after a known change and a recent, reliable backup is available.

However, restoring a backup can also overwrite data created after the backup, such as:

• orders
• form submissions
• user registrations
• content changes
• subscription data
• configuration updates

For an ecommerce, membership or business website, do not restore a backup without first understanding what data may be lost.

D4Hub can help you evaluate whether a restore is appropriate and how to preserve more recent data.

What should you avoid doing?

When a website is unavailable, it is tempting to try every possible solution quickly. This can make the original problem harder to identify.

Avoid:

• updating all plugins at once
• deleting plugins without a backup
• changing the PHP version repeatedly
• restoring an old backup without checking its date
• copying code found in forums without understanding it
• editing the database
• replacing WordPress files at random
• making several changes before testing the result

Try to change only one thing at a time and keep a record of what you did.

If you are unsure, stopping is often safer than continuing.

D4Hub can take over the investigation from any point, including after an unsuccessful troubleshooting attempt.

When should you ask for technical support?

Technical support is recommended when:

• the entire website is unavailable
• the problem affects checkout, payments or subscriptions
• the website contains customer or business data
• you do not have a verified backup
• you cannot access the dashboard
• the error returns after a temporary fix
• you suspect a plugin conflict but cannot identify it
• custom code is involved
• the error appeared during a migration or restore
• the hosting provider says the issue is inside WordPress
• you are not confident editing files or changing server settings

You do not need to diagnose the issue yourself before asking for help.

A useful support request can simply explain:

• what you were doing
• what changed
• what you can currently access
• what is no longer working

What information should you collect?

Before opening a support request, collect whatever information is easily available.

Useful details include:

• the website URL
• a screenshot of the error
• the approximate time the problem started
• what happened immediately before the error
• whether the public website works
• whether the WordPress dashboard works
• which pages or functions are affected
• any email received from WordPress
• the name of the hosting provider
• whether a recent backup is available

Do not worry if you cannot provide everything.

D4Hub can help you understand what additional information or access is needed.

How D4Hub can help

The objective is not just to make the error message disappear.

A proper investigation should identify the cause, restore the necessary functionality and reduce the risk that the same issue appears again.

Depending on the problem, D4Hub can help with:

• checking recent updates and website changes
• identifying the plugin, theme or custom function involved
• reviewing the available error information
• safely deactivating problematic components
• checking compatibility between WordPress, plugins and PHP
• restoring damaged or missing files
• evaluating whether a backup should be restored
• coordinating with the hosting provider
• testing forms, login, checkout and other important functions
• recommending preventive updates or maintenance

You can ask for support at any stage of the process.

For example, D4Hub can:

• guide you through a simple check
• verify whether an action is safe
• take over when the dashboard is inaccessible
• complete the full diagnosis and repair
• review the website after a temporary fix

If any step in this guide feels unclear or potentially risky, you do not need to perform it alone.

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