Critical Errors and Blank Pages

White screens, PHP errors, and getting back into a site you can't reach.

A white screen, or the message "There has been a critical error on this website", means PHP stopped running. The message alone almost never says why, so the job is to narrow it down quickly.

None of this deletes anything. Everything below is reversible.

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First: find out what the error actually says

WordPress hides the details from visitors by default. Turning the log on takes a minute and usually names the exact file and line.

Add these two lines to wp-config.php, above the line that says /* That's all, stop editing! */:

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

Reload the page that fails, then open wp-content/debug.log. The last entries name the cause.

Remove these lines when you're done. Leaving debugging on can expose information about your site to visitors.

Also check Kalium -> Status if you can reach your admin: Kalium needs PHP 7.4 or newer and at least 128 MB of memory.

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The whole site is down

You'll need FTP access or your host's file manager for this.

Step 1, rule out plugins

1. Rename the folder wp-content/plugins to plugins-off

2. Reload your site

If the site comes back, a plugin is the cause. Rename the folder back to plugins, then go to Plugins in your admin and disable them one at a time until the problem returns.

Step 2, rule out the theme

If the site is still down:

1. Rename wp-content/themes/kalium to kalium-old

2. Download a fresh copy of the theme from your Laborator account

3. Upload it as kalium

4. Reload

Renaming the plugins folder disables everything at once. It's the fastest way to answer "is it a plugin?" Nothing is lost; your settings are all in the database and come back when you rename the folder.

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The site works but I can't reach the admin

1. Disable all plugins by renaming wp-content/plugins over FTP

2. Log in

3. Rename the folder back and reactivate plugins one at a time

If that doesn't work, rename the Kalium folder so WordPress falls back to a default theme, log in, then reinstall Kalium from your account.

If a code snippet is the cause, there's a faster way in. Add this to wp-config.php:

define( 'KALIUM_SNIPPETS_SAFE_MODE', true );

Every snippet stops running and your admin is reachable again. Remove the line once you've fixed the snippet.

When a Snippet Goes Wrong

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One page is blank but the rest of the site works

This is rarely a real error, usually something is deliberately replacing that page.

Check first:

1. Is a Template Part replacing it? Open Kalium -> Template Parts and look for a Page type whose display conditions match that page.

2. Was the page built with a page builder that's now inactive? A page built in WPBakery or Elementor shows nothing if the plugin is disabled.

Disable the matching template part, or reactivate the builder plugin, and reload.

A Setting Isn't Working

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Only the portfolio breaks

This is Advanced Custom Fields Pro being inactive, in almost every case.

ACF Pro is bundled with Kalium and powers the portfolio's settings. Install and activate it from Kalium -> Plugins.

Plugin Problems and Conflicts

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PHP version errors

An error mentioning a PHP version, or a TypeError, usually means your host upgraded PHP underneath you.

1. Check Kalium -> Status for your PHP version

2. Update Kalium and all its bundled plugins, the latest versions carry the compatibility fixes

3. If the site is down and you can't reach the admin, ask your host to move PHP back one version temporarily, then update

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If you get the site back

Once it's running again, work out what caused it before carrying on:

• A plugin: check whether it has an update, or find an alternative

• A code snippet: check the Template Parts list for one showing an Error status

• The update didn't finish: check Kalium -> Status shows the version you expect

• Server limits: ask your host to raise the memory limit to 256 MB

Bad Hosting Environment