WordPress not working after update: symptom, cause and going back to the previous version
When WordPress is not working after an update, the cause is usually one plugin, the theme or a PHP version that is too old. First recognise the symptom: a white screen, a critical error, a stuck maintenance message or a broken layout. Then deactivate or roll back the last updated item. In a shop, check the cart and an order before you call it done.
Author: The TellMyShop team. A guide for WordPress site and WooCommerce store owners: the cause, the manual fix and the same work in a chat conversation.
Last updated: · 6 min read
The symptom points to the cause
After an update, a site can break in several ways. Each one points to a different cause and a different first move.
| What you see | Most common cause | First move |
|---|---|---|
| “There has been a critical error on this website” or a white screen | the new plugin version doesn't work with another plugin or with the PHP version | deactivate the updated plugin: the recovery mode email or the file manager |
| A scheduled maintenance message that won't go away | the update was interrupted halfway | delete the .maintenance file in the site's root folder |
| The site works, but the layout is broken | old style files in the cache | clear the cache in the plugin, the browser and the CDN |
| Everything works except the cart or payment | an update of WooCommerce, a payment gateway or the shop theme | check the logs and versions; roll back that plugin if needed |
| The dashboard works but the site doesn't (or the other way round) | an error in the part of the code that only loads there | the error logs point to the file and plugin |
If you see a critical error across the whole site, there is a separate rescue guide in the article on the WordPress critical error. Here we focus on what to do when you know an update is to blame, and how to go back to the previous version.
Tuesday after the update: how to work out what changed
A typical situation: seven updates are waiting in the dashboard, you tick them all and click update. A few minutes later a friend writes that she can't pay in the shop. You need to work out which of the seven plugins did it.
Memory fails, so look for traces. Plugins with automatic updates turned on may have changed overnight too, without you clicking anything. Error messages contain a file path, and in it the name of the plugin folder. Hosts usually show the PHP error log in their panel. If you run a shop, WooCommerce records fatal errors in its own logs in the shop status section.
When the traces tell you nothing, deactivate the updated plugins one at a time and check the site after each. Start with those that touch the problem: for the cart, WooCommerce and payment gateways; for the layout, the theme and page builder.
How to roll back a plugin update step by step
Deactivating a plugin puts out the fire. But you often need that plugin, so you want to go back to the version that worked.
- Note which version you had. The old version number is in the automatic update email, in the plugin's changelog or in the backup.
- A plugin from the wordpress.org directory: install WP Rollback. Under each directory plugin, a link appears for choosing an older version. The WPBeginner guide to rolling back plugins shows what this looks like. WP Rollback can't roll back paid plugins from outside the directory.
- A paid plugin: download an older ZIP file from your account with the plugin author and upload it in place of the current version, or ask whoever looks after the site to do it.
- The host's backup: if you run a shop, ask for only the plugin files to be restored, without the database. Restoring the database will wipe orders placed after the backup was made.
- Turn off automatic updates for that one plugin on the plugin list, so the broken version doesn't come back tomorrow. Turn them back on when the author releases a fix.
- Check the site as a customer: the homepage, a post, and in a shop a product, the cart and a test order.
There is a description of finding the guilty plugin by deactivating them in the cyber_Folks guide to plugin conflicts (in Polish).
What WordPress does by itself, and what it doesn't
Since version 6.6, after an automatic plugin update WordPress checks the homepage. When it returns a critical error, it restores the previous version and emails the administrator. You will find a description of this feature in the DreamHost article on automatic update rollback.
This net has wide gaps. It doesn't cover updates clicked by hand or themes. It also won't notice an error that only breaks the cart, payment or the layout, because it checks just the homepage. So with a shop, checking the cart after an update remains your job.
How the chat helps after an update
When only part of the site is broken and the dashboard responds, your chat (Claude or ChatGPT) helps you work out what changed. With an error across the whole site, the TellMyShop plugin for WordPress and WooCommerce won't start, because it runs inside WordPress, so the routes described above remain.
It reads the error logs, groups repeated messages and names the plugin or theme each one comes from. It shows the plugin list with versions, automatic updates and the required PHP version, as well as the site health. All of this works in the free TellMyShop Free.
You: Since yesterday's updates the cart doesn't work. What broke?
Your chat: The logs have a new critical error, 12 occurrences since yesterday. It comes from the Example Cart Add-ons plugin, version 5.0, updated automatically. The other six updated plugins have no errors.
Your chat: I suggest deactivating this plugin and restoring the older version from a backup or your account with the author. Preview:
You: Yes, deactivate it.
Your chat: Deactivated. The homepage responds. Check the cart with a test order. You can undo the change from the change history.
Card status: waiting for your “yes”old version: Example Cart Add-ons: active
new version: Example Cart Add-ons: inactive
Deactivating, activating and updating plugins works in TellMyShop Pro after you turn on the Plugins switch in the panel. The switch lasts 24 hours and requires a database backup made the same day. For an update, the preview shows the current and new version, part of the changelog and warnings: a major version change, a WooCommerce or payment gateway update. It updates at most 5 plugins at once and checks the homepage after each one.
There are two limits: the chat won't roll back a plugin update automatically, and the TellMyShop plugin doesn't make backups of the whole site. The previous version is restored by the host's backup or by installing an older version. You undo a plugin deactivation made by the chat from the change history.
Before you next click Update
These habits save nerves and don't need a developer:
- Update a few plugins at a time, not all at once. It is easier to spot the culprit.
- Before updating, check that your host has a fresh backup, and know how to restore it.
- Do major version changes (for example from 4.x to 5.0) and WooCommerce updates when you have time to check the shop.
- After updating, place a test order or ask the chat for a morning review with new errors from the logs.
You can read how the chat reads logs and site health on the TellMyShop for WordPress and WooCommerce page. You can compare licences in the pricing, and find more guides on the blog.
Questions and answers
How do I roll back a WordPress plugin update?
For plugins from the wordpress.org directory, the simplest way is the WP Rollback plugin, which installs a chosen older version. You roll back a paid plugin by uploading an older ZIP file from its author. When the dashboard doesn't work, first deactivate the plugin through the hosting file manager, then roll back the version.
The site shows a maintenance message that won't go away. What do I do?
It means the update was interrupted halfway. WordPress left a .maintenance file in the site's root folder. Delete it in the hosting file manager, refresh the site and repeat the update of the plugin that didn't finish.
Does WordPress roll back failed updates by itself?
Partly. Since version 6.6, WordPress rolls back an automatic plugin update when the homepage returns a critical error right after it. This doesn't cover updates you clicked by hand, themes, or errors that break the look, the cart or other pages.
The site looks broken after an update, but it works. Where do I start?
Clear the cache in your cache plugin and the browser, and if you use a CDN-type service, there too. Old style files often stay in the cache after a theme or page builder update. If that doesn't help, check which plugin or theme was updated most recently.
Will the chat roll back a plugin update?
Not automatically. The chat points out in the logs and the plugin list what caused the problem, and in TellMyShop Pro, after you turn on the Plugins switch, it can deactivate that plugin. The previous version is restored by the host's backup or by installing an older version.
WordPress is a trademark of the WordPress Foundation. WooCommerce is a trademark of Automattic Inc. Claude is a trademark of Anthropic PBC. ChatGPT and OpenAI are trademarks of OpenAI. TellMyShop is not affiliated with these companies.