WordPress critical error and white screen, causes and fix

You open your site and, instead of it, you see the message "There has been a critical error on this website" or simply a blank, white page with no content. The admin panel often stops working too. It is one of the most common and most stressful WordPress failures, because it looks as if the whole site has vanished. The good news: in most cases it can be fixed, and the data is intact. Below we explain what this error means, where it starts, and how to remove it step by step, without doing more damage in the process.

What "There has been a critical error on this website" means

It is the message WordPress uses to hide a serious PHP error so it does not show visitors the technical details. In the past, this was simply the "White Screen of Death", a blank page. The meaning is the same: the code that builds the page stopped halfway and cannot finish. Most often a single specific plugin, theme, or a lack of memory is to blame, not "the whole of WordPress".

If instead you see a blunt "HTTP ERROR 500", that is a slightly different path, we describe it in a separate post on the 500 error (Internal Server Error).

An important clue: WordPress usually sends the administrator's email an message titled "Your Site is Experiencing a Technical Issue". Inside there is often the name of the plugin or file that triggered the error, plus a special link to recovery mode. Check there first, it is often a ready-made answer to what broke.

The most common causes

A plugin update or conflict. By far the most common reason. A plugin, after an update, clashes with another or with the server's PHP version and takes down the whole site.
The theme. The same mechanism as with plugins: a theme update or a corrupted theme file can stop the page from rendering.
Too low a PHP memory limit. On larger sites the server simply cannot build the page within the allocated memory and aborts.
A PHP version change on the host. An older plugin or theme does not work on the new PHP, which shows up as a critical error overnight, even when you changed nothing.
A corrupted core file or a sign of a hack. Less often, but it happens: replaced or injected malicious code also ends in a white page. More on that below.

Before you start: make a backup

Whatever you are about to do, first back up the files and the database, even just through the hosting panel. Fixing a failure without a backup is working without a safety net: if something goes wrong, there is no way back. If you are not sure how, we have it laid out in a separate post on website backups.

How to fix it step by step

Start with the simplest. After each step, refresh the site and check whether the error is gone.

Check the admin email and recovery mode. If WordPress sent the technical issue message, click the recovery mode link. You will enter the panel in a safe mode and disable the element that triggered the error.
Disable plugins, even without panel access. Through the file manager in your hosting panel or FTP, rename the wp-content/plugins folder to, say, plugins-off. That deactivates all plugins at once. If the site comes up, one of them is to blame. Restore the folder name and enable the plugins one by one until you hit the one that breaks it.
Switch the theme to the default. If the plugins are not the issue, rename the active theme in the wp-content/themes folder. WordPress will fall back to the default theme. If that helps, the problem is in your theme.
Increase the PHP memory limit. In wp-config.php add the line define('WP_MEMORY_LIMIT', '256M');. If the error came from a lack of memory, the site will start.
Enable the error log. In wp-config.php set define('WP_DEBUG', true); and define('WP_DEBUG_LOG', true);. Errors will be saved to wp-content/debug.log with the exact file and line that fails. It is the fastest route to the cause. After the diagnosis, remember to turn debug off, it should not be enabled on a live site.
Check the PHP version. In your hosting panel, see whether the PHP version changed recently. Reverting to the previous one is often a quick workaround before you update the vulnerable component.

When a white screen is a sign of a hack

If the error remains after disabling all plugins and switching the theme, or you see foreign, unreadable code in the files (long strings of characters, eval, base64_decode), then it is not an ordinary failure but a possible sign of infection. In that case it is no longer about fixing one file but finding and closing the gap someone used. Start with a free website infection test, and if it confirms the problem, remember that removing the malicious code alone, without closing the gap, makes the infection come back within days.

When to hand it to a specialist

If you have no file access, the log does not point to a clear cause, or you are afraid of breaking more while poking around, it is a sensible moment to hand it to someone who deals with such failures every day. This is exactly what we do: a site that is not working. We diagnose for free, work on a copy, and tell you plainly what happened and how long the fix will take.

Frequently asked questions

Do I lose data and content with a critical error?

No. This error stops the page from displaying, but it does not delete posts, images, or settings, they sit in the database and in the files. That is why the fix is about removing the cause, not rebuilding the site from scratch.

The site worked yesterday, today a white screen, though I changed nothing. How is that possible?

Most often the server changed, usually the PHP version, or an automatic plugin or theme update installed in the background. From your perspective "nothing happened", yet something switched underneath.

I have no access to the WordPress panel. Can anything be done?

Yes. Most of the steps above (disabling plugins, switching the theme, editing wp-config.php, the error log) are done at the file level through the file manager in your hosting panel or FTP, without entering the WordPress panel.

How long does fixing a critical error take?

Typical cases, where a single plugin or memory is to blame, are solved in a dozen minutes to an hour. It is harder when a conflict of several components or an infection is involved, because you have to find the source, not just disable the symptom.