WordPress Update Disasters: 7 Common Failures and How to Prevent Them

If a WordPress update broke your site, you are not alone. Most WordPress update disasters come from a short list of causes: a plugin that clashes with another plugin or your theme, a PHP version your code was not built for, theme edits that get overwritten, and updates that stop halfway. Two habits prevent most of them: keep a recent backup you know how to restore, and try updates on a staging copy of your site before they reach the live one.

Below are seven common failures and how to prevent each, then how to recover when one happens anyway.

Why do WordPress updates break websites?

Updates break sites because each one changes code that other code depends on. Your site is WordPress itself, a theme and a set of plugins from different developers, all running on your host's version of PHP (the programming language WordPress is written in). Each developer tests their own product; nobody tests your exact combination.

Skipping updates is not the answer, because updates carry security fixes. The goal is to catch a problem before your customers do.

What are the 7 most common WordPress update failures?

1. A plugin update clashes with another plugin or your theme

A menu stops opening, a layout shifts, a contact form stops sending, or the whole site shows "There has been a critical error on this website." The quiet failures cost the most, because nobody notices for days.

Update one plugin at a time, so you know which change caused a problem, and test on staging first. Each plugin's WordPress.org page lists the WordPress version it was tested up to and the PHP version it needs.

2. Your server moves to a newer PHP version

Hosts retire old PHP versions, and an older plugin or theme may contain code that newer PHP rejects, usually producing the critical error screen. This can happen without you updating anything. It also works the other way: WordPress 7.0, released in May 2026, needs at least PHP 7.4. The PHP section below explains how to check.

3. A theme update wipes out your changes

If someone edited your theme's files directly, the next theme update replaces them and the edits are gone. Keep code changes in a child theme, a small add-on theme that holds your changes while the main (parent) theme updates safely. If you inherited the site, find out where its changes live before updating the theme.

4. An interrupted update leaves the site in maintenance mode

While WordPress installs an update, it places a file named .maintenance in the site's main folder, and visitors see "Briefly unavailable for scheduled maintenance. Check back in a minute." If the update stops partway, the message can stay.

WordPress ignores that file after ten minutes, but the update may not have finished. Delete .maintenance using SFTP or your host's file manager, then run the update again from Dashboard > Updates.

5. A database update step is skipped or fails

Some updates change how data is stored, so the database needs updating after the files. WordPress links to this step when a release needs it, and WooCommerce shows an "Update WooCommerce Database" button. Until it runs, the new code and your stored data do not match. Back up immediately before, run it on staging first, and finish it before you check the site.

6. WooCommerce template overrides go out of date

Many themes carry their own copies of WooCommerce's templates, the files that build the cart, checkout and other store pages. When WooCommerce changes its templates, those copies fall behind and store pages can misbehave. WooCommerce > Status > System Status lists your theme's overrides at the end and flags outdated ones. The fix is usually a theme update, or a request to the theme's developer.

7. An automatic update runs while nobody is watching

On most sites, WordPress applies its maintenance and security releases automatically, and since version 5.6, new sites also auto-update to major releases by default. Plugin and theme auto-updates, switched on one by one, run twice a day. If one breaks something overnight, the first person to notice may be a customer, so make sure the admin email address, which receives the update reports, belongs to someone who reads it.

What should you do if a WordPress update broke your site?

Undo the one change that caused the problem if you can identify it; otherwise, restore the backup you took before updating.

• Check the admin email. Since WordPress 5.2, a fatal error from a plugin or theme triggers an email to the admin address naming the cause, with a recovery mode link. The link opens your dashboard with the faulty plugin or theme paused so you can deactivate it, and it expires after one day by default.
• Rename the plugin's folder. With no email and no login, use SFTP or your host's file manager to open wp-content/plugins and rename the plugin's folder (adding "-old" works). WordPress deactivates it.
• Restore the backup if you cannot find the cause. On a store, restoring the database also removes orders placed since that backup, so note them first.
• Clear your caches afterward, or visitors may keep seeing the broken version.

What is a staging site, and does a small business need one?

A staging site is a private copy of your website at a separate address, where you can try updates without visitors seeing them. If your site takes orders, bookings or leads, it is worth having: it lets you find a broken checkout or form before a customer does.

There are three common ways to get one:

• Your host's staging tool. Many hosts include one: you create the copy, test, then push changes live. SiteGround, for example, includes it on its GrowBig and GoGeek plans.
• A staging plugin. WP Staging's free version copies your site into a subfolder of your hosting; pushing changes back to live needs the paid Pro version.
• A copy on your computer. Free apps such as Local (by WP Engine) and WordPress Studio (by Automattic) run WordPress on your own machine. Developers build there, test on staging, then publish live. For checking updates, staging on your host is more useful, because payments, emails and connected services are hard to test on a computer.

On a store, never push a staging database over the live site: orders and customer accounts created since you made the copy would be overwritten. Push files only, or repeat the tested updates on live. Keep the copy private too: it holds customer data, so password-protect it, tell search engines not to index it, and put payment gateways in test mode.

What is the safest way to update WordPress?

Back up, test on staging, then repeat the same updates on the live site at a quiet time:

• Take a fresh backup of files and database.
• Refresh staging from the live site so you test against current content.
• Update one item at a time. For stores, WooCommerce's guide says to update WooCommerce first, run its database update, then update extensions, the theme and payment plugins.
• After each update, send a test form, place a test order, try a booking and log in as a customer, on a phone as well as a computer.
• Apply the updates to the live site when traffic is low, clear caches, and check those pages again.

Should you turn on WordPress auto-updates?

Leave the automatic maintenance and security releases on, and decide plugin auto-updates one plugin at a time. Small, well-maintained plugins are usually fine. Plugins that run your checkout, payments, forms or page layout are better updated by hand after a staging test.

WordPress 6.6 added a safety net: if a plugin's automatic update causes a PHP fatal error on your homepage, WordPress restores the previous version and emails the admin. It only catches that one kind of failure; a shifted layout or a checkout that quietly stops working will not trigger it.

How do you check whether your site is ready for a newer PHP version?

Find your version under Tools > Site Health, on the Info tab, then test the newer version on staging before the live site moves. As of October 2026:

• WordPress 7.0 and later need PHP 7.4 or newer, and WordPress.org recommends 8.3 or greater. Sites on PHP 7.2 or 7.3 stay on WordPress 6.9.
• PHP 8.1 and older no longer get security fixes, and security support for PHP 8.2 ends on December 31, 2026.

Switch the staging copy to the newer PHP version in your hosting dashboard (or ask your host), then click through the key pages. Skip the old PHP Compatibility Checker plugin: it is no longer maintained and only checks up to PHP 8.0. If the live site breaks after a switch, ask your host to go back to the previous version.

Who can handle WordPress updates for you?

A maintenance service can, if you would rather not do this yourself. WP Resolve's care plans start with Essential Care at $79 a month: weekly core, theme and plugin updates with visual checks, and daily off-site backups kept 30 days. Business Care ($149 a month) adds updates tested on a staging copy first, and Commerce Care ($199 a month) also tests WooCommerce, payment and shipping plugins on staging.

If an update has already broken your site, our Emergency Fix is a flat $199 with a 24-hour turnaround, and no plan is needed.

Not sure where your updates and backups stand? Ask for a free site health check covering updates, backups, security and speed, or text (916) 209-0917.

Frequently asked questions