WordPress white screen of death: find the cause and fix it (with or without AI)

A WordPress white screen of death is almost always a plugin or theme that crashed PHP, the language WordPress runs on. Switch that plugin or theme off and the site comes back. Below you can find it by hand, or let an AI app do it while the site is down.

What the white screen means

Visitors see a blank page, or the message “There has been a critical error on this website”. Behind both is a fatal error: PHP hit code it couldn’t run and stopped. Your posts and products are still in the database. The page just can’t be built.

Sometimes only wp-admin is white, or only one page. The cause is the same kind of code, in a part of the site that loads only there.

The usual causes

• A plugin or theme update. The new version has a bug, or doesn’t fit your PHP or WordPress version.
• A code edit. A snippet pasted into functions.php, or a missing bracket.
• A new PHP version. Your host upgrades PHP and an old plugin can’t run on it.
• Memory. PHP stops with “Allowed memory size exhausted” when a page needs more than it may use.
• A clash. Two plugins that conflict, or an update that stopped halfway.

Fix the WordPress white screen of death by hand

Go from the gentlest step to the roughest. Copy a file or folder before you rename or edit it.

1. Look for the recovery-mode e-mail. When WordPress detects a fatal error, it e-mails a recovery link to the administrator address (Settings › General). The link opens a safe mode that pauses the broken plugin or theme, and you can switch it off there. Check your spam folder, because WordPress limits how often it sends this e-mail.
2. Read the error. In wp-config.php, set WP_DEBUG and WP_DEBUG_LOG to true and WP_DEBUG_DISPLAY to false, so visitors see no errors. Reload the page and open wp-content/debug.log. The newest “PHP Fatal error” line names a file. A path such as wp-content/plugins/gallery-pro/… points at the plugin gallery-pro. Set debug back to false afterwards.
3. Rename the plugin’s folder. With FTP or your host’s file manager, open wp-content/plugins and rename the folder, for example gallery-pro to gallery-pro-off. WordPress treats a missing plugin as switched off. If you don’t know the culprit, rename the whole plugins folder. Once the site loads, rename it back and activate plugins one at a time until the white screen returns.
4. Switch the theme. Rename the active theme’s folder in wp-content/themes. WordPress falls back to a default theme if one is installed.
5. Raise the memory limit if the log says memory is exhausted. Set WP_MEMORY_LIMIT to 256M in wp-config.php, or ask your host. A higher limit can hide a heavy plugin instead of fixing it.
6. Check the PHP version. If the trouble began when your host changed PHP, switch back in the hosting panel. Then update or replace the plugin that can’t run on the newer version.

If nothing works, restore a backup from your host. Do that last.

How an AI app does it with rescue mode

The manual route needs file access and some nerve. The AI route needs one thing: your app must be connected before the crash. PowerWP AI’s rescue mode is the part that still works while the site is down.

It relies on a small must-use plugin, the rescue loader, which WordPress loads before your regular plugins. If WordPress hits a fatal error while starting up for a request from your AI app, rescue mode switches on for 30 minutes. The first request fails with a message that names the error.

The retry runs with only PowerWP AI loaded: none of your other plugins, and not your theme. Visitors still see the error until the cause is fixed. Meanwhile the app follows the same path you would:

1. It reads the debug log and the PHP error log and finds the file that crashed.
2. It checks the change log and recently modified files for what changed.
3. It tells you the smallest fix and what it would affect, and waits for your OK.
4. It sets a checkpoint, then rolls the change back or deactivates the plugin.
5. It tests the normal site, checks the home page and the failing address, reads the log for new fatal errors, and switches rescue mode off.

Example on the demo store your-store.com. You write:

My site shows “There has been a critical error” on https://your-store.com/shop/. Find out why. Don’t change anything yet.

The app reports that the newest fatal error comes from the plugin gallery-pro. It proposes to deactivate it, and waits for you.

The fix is recorded in PowerWP AI › Changes. A plugin the app deactivated can be switched on again by rolling back that change. Do that only after its developer has fixed the cause, or the site crashes again. The critical error guide lists each step with a prompt you can paste.

What rescue mode can’t do

• It helps only an app that was connected before the crash.
• It works for apps that connect with a key and for apps that signed in, such as Claude and ChatGPT.
• If PowerWP AI itself can’t load, the app can’t reach the site. Use the recovery e-mail link or your hosting panel.
• It needs a writable wp-content/mu-plugins folder to install its loader. It doesn’t switch off must-use plugins.
• It doesn’t repair anything by itself. It gives the app a way in, and you approve the fix.
• On the Free plan the app can read the error and name the cause, but you apply the fix yourself.

Stop the next white screen

Changes your AI app makes through PowerWP AI get an automatic health check. After a plugin, theme or code-file change, PowerWP AI reloads your site and reverts the change if it now shows a fatal error. A crash from an update started in wp-admin, or an automatic update, isn’t covered. Rescue mode is for those.

Update one plugin at a time, with a backup first, as in update plugins and themes safely. The safety page shows how the layers fit together.

Questions

Is the white screen of death a hack?

Most come from a plugin, a theme, a PHP change or memory. A hack can cause one too, so if the log names a file you don’t recognize, run a security check before you fix it.

Will I lose my content?

Normally no. A white screen means PHP stopped running. It doesn’t delete your posts, products or orders, which stay in the database. Take a backup before you fix anyway.

How do I fix the white screen if I can’t log in to wp-admin?

Use the recovery link from the e-mail, or rename the plugin or theme folder by FTP or your host’s file manager. Or ask your AI app, if it was connected before the crash.

Can the AI make it worse?

It can make a mistake, so it tells you its smallest fix first and waits for your OK. It sets a checkpoint, and the change is recorded, so you can roll it back.

Try it on your own site. Connect your AI app while the site is healthy, so it can help on the day it crashes. The Free plan is read-only: your AI app can look at everything and change nothing, with no card and no end date. When you want it to fix things, upgrade with the same key.