My WP plugin stopped working. Is it a conflict?

A plugin not working means it's switched on but doesn't do its job, most often because another plugin or your theme gets in its way.

• It clashes with another plugin, for example when both load their own copy of the same script, or use the same function name.
• It clashes with your theme, which changes the same part of the page the plugin needs.
• 2 plugins do the same job, such as 2 cache or 2 SEO plugins, and undo each other's settings.
• It needs a newer WP, or a newer PHP (the language WP runs on), than your site has. Its wordpress.org page lists what it needs.
• A recent update, to it or to another plugin, changed how it works.
• A cache still serves old files, so a change you made doesn't show.
• Nobody looks after it anymore, so it hasn't kept up with newer WP versions.
• A setting is missing, for example a contact form with no address to send its email to.

Find the cause

Start with what changed. Did you add, update or switch on a plugin the day it stopped working? Test that one first.

Test on a copy of your site if your host offers one, often called staging. On a copy, you can switch plugins off and your visitors won't notice. No copy? Pick a quiet hour.

Switching a plugin off is the right tool for this test. Its settings stay in your database, and Activate brings it back as it was. Don't delete plugins to test them: some remove their settings and content when you do.

Switch the others off, then back on

In Plugins › Installed Plugins, tick every plugin except the one that isn't working. Pick Deactivate in Bulk actions and press Apply. Write down which ones you switched off.

Test the broken thing again. If it works now, one of those plugins clashes with it. Switch them back on one at a time, and test after each. The one that breaks it again is the clash.

Have 20 or more plugins? Switch half of them back on at once. If it breaks, the clash is in that half. Split that half again, and keep going until one plugin is left.

Test your theme

Still broken with every other plugin off? Try your theme. Write down which theme you use, then activate a default theme, such as Twenty Twenty-Five, in Appearance › Themes. Test again, then switch back.

Test without your visitors seeing it

The free Health Check & Troubleshooting plugin, from the WP community at wordpress.org, has a Troubleshooting Mode. It switches plugins off for you only, while your visitors still see your normal site.

Read the errors

Your error log often names the plugin. Look for a line with “PHP Fatal error” or “PHP Warning” in it. The folder after wp-content/plugins/ in its path is the plugin. Many hosts show this log in their control panel, often under Logs.

No log there? Add define( 'WP_DEBUG', true ); and define( 'WP_DEBUG_LOG', true ); to wp-config.php, above “That's all, stop editing!”. Reload the page, then open wp-content/debug.log. Take both lines out when you're done.

Some clashes only show in your browser. Right-click the page, pick Inspect, and open the Console tab. A red line often names a file, and its path shows the plugin folder.

Fix it by cause

Two plugins clash

Look for a setting in either plugin that turns off the part they share, such as a script or a style. If there isn't one, keep the plugin you need most and find another for the other job.

Then tell both authors in their support forums on wordpress.org. Give your WP version, both plugin names and the error line. Leave out passwords and anything from wp-config.php.

Two plugins do the same job

2 cache plugins, or 2 SEO plugins, fight over the same settings. Keep one, switch the other off, and delete it once you're sure you don't need it.

It needs a newer WP or PHP

PHP is the language WP runs on; your host sets its version. Yours is in Tools › Site Health, on the Info tab under Server. If it's lower than the plugin needs, ask your host to move you up.

An update brought it

Go back to the version that worked. Most plugins in the WP plugin directory list older releases on their Advanced View page, under Previous Versions. Our page on a plugin update that crashed a site walks through it.

With CMSHands, ask the chat for the version that worked. You see the swap before anything changes, and it uses versions wordpress.org still has.

A cache serves old files

Clear your cache plugin's cache, then your host's, if they have one. Then reload the page with your browser's cache skipped: Ctrl+Shift+R, or Cmd+Shift+R on a Mac.

Nobody looks after it

Open its wordpress.org page and check Last updated and Tested up to. If it hasn't been updated in a long time, look for another plugin that does the same job and still gets updates.

With CMSHands, ask if a plugin is still looked after. It checks the plugin's listing at wordpress.org.

Stop it coming back

Add or update one plugin at a time, and check your site after each. If something breaks, you know which one did it. Keep fewer plugins: each one you remove is one less to clash.

With CMSHands on your site, you can run the same test in its chat. Ask it to switch a plugin off, and it shows a card first: a box in the chat that shows exactly what would change. Press Undo and the plugin is back on.

We tried it on our test site, a WP site we run to try every task before we write about it. On Oct 14, 2026, we asked it to switch off Flamingo, a plugin that saves contact form messages.

Before we pressed Switch it off, it said what that would change: messages stop being saved in WP, and the form still sends email. After, it checked the change was in place. Undo switched Flamingo back on, and the contact form loaded each time.

It also reads your error log when you ask “What are the errors on my site?”