"There has been a critical error on this website": how to fix it

What the error means

WordPress shows this message when some PHP code on your site hits a fatal error. The most common causes are:

• a plugin or theme update that doesn't agree with another plugin;
• your host upgrading the PHP version, which older plugins can't handle;
• a half-finished update, or files that have been edited or damaged.

Step 1: check the site admin's inbox

When this happens, WordPress normally emails the site's admin email address with the subject "Your Site is Experiencing a Technical Issue". The email says which plugin or theme caused the problem and includes a special recovery mode link.

Click the link and log in. WordPress lets you into the dashboard with the broken plugin paused. Go to Plugins, deactivate the one named in the email, then exit recovery mode. The recovery link only works for a limited time, so use it promptly.

Step 2: no email? Check spam, then check who gets it

Look in spam or junk. Then check which address the email went to. It goes to the admin email set in Settings → General, which is often an old address or the developer who built the site. If your site can't send email at all, the recovery email won't arrive either.

Step 3: turn the plugin off without the dashboard

If you can't get into the dashboard, you can switch a plugin off through your hosting control panel's File Manager (or FTP):

1. Open wp-content/plugins/.
2. Rename the folder of the plugin you suspect, for example contact-form to contact-form-off. WordPress will then treat it as deactivated.
3. Not sure which plugin it is? Rename the whole plugins folder to plugins-off. If the site comes back, rename it back and switch plugins on again one at a time from the dashboard until the error returns.

Before you change anything, take a backup (most hosting control panels have one-click backups) and write down what you've renamed.

Step 4: read the error log

If it's still broken, the error log names the exact file and line. Your hosting control panel usually shows PHP error logs. Otherwise, whoever manages your site can switch on WordPress's debug log. That tells you what broke, instead of guessing.

How to stop it happening again

• Keep a working, tested backup. See our guide: how to test your website backup.
• Update plugins regularly rather than all at once after months, and delete plugins you don't use.
• Make sure the admin email in Settings → General goes to an inbox someone actually reads.