The WordPress white screen

The white screen — WSoD, the white screen of death — means PHP stopped executing before anything reached the browser. The server answered correctly; there is simply no content. The good news is that the list of causes is short, and you can walk it in order.

Turn on error reporting first

Without this step you are guessing. Open wp-config.php in the site root and, just above the line commented /* That's all, stop editing! */, add:

define('WP_DEBUG', true);
define('WP_DEBUG_LOG', true);
define('WP_DEBUG_DISPLAY', false);

Reload the page, then open wp-content/debug.log. You will find a message with a file name and a line number, which usually names the culprit straight away.

Why set WP_DEBUG_DISPLAY to false? Because error messages can expose server paths and fragments of your configuration. Writing to a file is seen only by you; printing on the page is seen by every visitor.

Check the plugins

In the vast majority of cases the white screen appears right after a plugin or theme update. If you can still reach the admin panel, disable plugins one by one. If the panel is blank too, do it over FTP or SSH:

1. Rename wp-content/plugins to plugins-off. That disables every plugin at once.
2. Check the site. If it is back, a plugin is responsible.
3. Restore the directory name, then rename individual plugin directories until you find the one that breaks the site.

If the site is still blank with every plugin disabled, test the theme the same way — rename its directory in wp-content/themes and WordPress will fall back to a default theme.

PHP memory limit

The second most common cause. The symptom can mislead: the site works, and the white screen shows only in the admin panel or on one particular page. In wp-config.php add:

define('WP_MEMORY_LIMIT', '256M');

If that helps, the problem is only parked, not solved. It is worth finding what consumes that much memory — usually a single plugin or an import of a large data set.

PHP version

After the server's PHP version changes, older plugins can stop working overnight. The log will then show a syntax error or a call to a function that no longer exists. Check which version your hosting panel has set and compare it with what your plugins require.

Rolling the PHP version back is a stopgap, not a destination — older versions stop receiving security fixes. It is better to update or replace the plugin that blocks the move forward.

A damaged core file

Less common, but it happens, particularly after an interrupted update. Download a clean WordPress package from the project site and overwrite the wp-admin and wp-includes directories. Do not overwrite wp-content or wp-config.php — that is where your content and configuration live.

Before you change anything

Take a copy of the files and the database. Every step above is reversible only while you have something to go back to. If the site earns money and you are not sure what you are doing, that is the moment to stop and ask for help.