How Do You Fix a WordPress Plugin Conflict?

While plugin conflicts in WordPress aren’t as common as they used to be, they can still happen. If your website suddenly crashes or behaves unexpectedly after activating a plugin, don’t worry – this guide will help you troubleshoot and resolve a wordpress plugin conflict.

One of the most frustrating errors for WordPress users is the infamous white screen of death. You install a plugin, click “activate,” and suddenly your site is gone—replaced with a blank screen or cryptic error messages.

This usually points to a plugin conflict. A plugin conflict happens when two plugins that work fine individually create errors when active at the same time. The conflict often arises because both plugins are trying to use the same PHP functions or libraries, leading to duplicate declarations.

In this article, you’ll learn practical steps to diagnose and fix these conflicts.

A Plugin Conflict Is Becoming More Rare

Thankfully, WordPress has improved its error-handling in recent years. When a plugin triggers a fatal error, WordPress often prevents the plugin from activating altogether. Instead, it displays an error notice and keeps the plugin inactive.

In most cases, you’ll see a message similar to:
“The plugin generated a fatal error and could not be activated.”

When this happens, it’s a good idea to test the plugin on a staging version of your site. If the plugin causes conflicts during testing and no fix is available, consider looking for an alternative that offers similar functionality but better compatibility.

Plugin conflicts are more likely to occur when:

You upload Must-Use (MU) plugins via FTP
Plugins or WordPress itself have been updated
Custom plugins are pushed to the live site

Let’s walk through how to troubleshoot and resolve these conflicts.

Do You Have Access To WordPress?

The first step in resolving any plugin conflict is determining whether you still have access to your WordPress dashboard.

If you do, the typical troubleshooting method is to deactivate all plugins and switch to a default theme (like Twenty Twenty-Four). This helps isolate the problem by ruling out plugin or theme interference.

However, doing this on a live site isn’t ideal – it can break important functionality.

Instead, install the Health Check & Troubleshooting plugin. This tool lets you temporarily disable plugins and switch themes for your user session only, without affecting the live site for other visitors.

Start with all plugins disabled
Reactivate them one at a time
Check after each activation to see if the problem returns
Save the theme for last, as custom themes may rely on plugin-specific features

Once you identify the faulty plugin, leave it deactivated and explore alternatives or contact the developer for support.

If You Don’t Have Access To WordPress

If the site is completely inaccessible—such as showing a white screen or server error—you’ll need to investigate at the server level.

The exact troubleshooting method depends on what access you have to the site files, hosting environment, and admin email.

Have Access To The Administrative Email? You May Get An Email

If your admin email is correctly set under Settings > General, WordPress may automatically send an error notification.

This email includes a link to enter Recovery Mode, which lets you safely log into the dashboard. Once inside, WordPress will indicate which plugin triggered the error so you can deactivate it.

This is one of the easiest ways to regain access and resolve the problem quickly.

Check The Host’s Log File

If email recovery isn’t an option, the next best step is checking the error logs provided by your hosting provider.

You can usually find these logs:

In your hosting dashboard
In cPanel under Metrics > Errors
Via FTP/SFTP access—look one directory level above /public_html/ or /www/ in a folder called /logs/

Search for a file named error_log and open it. Look for lines near the bottom that mention a “Fatal Error.” These logs will typically show the path and file where the conflict occurred, helping you pinpoint the faulty plugin.

No Logs? You May Need To Activate Them

If error logging isn’t active, you can enable it by editing your wp-config.php file.

Add the following lines near the bottom of the file (just above the line that says “That’s all, stop editing!”):

define( 'WP_DEBUG', true );
define( 'WP_DEBUG_LOG', true );
define( 'WP_DEBUG_DISPLAY', false );
@ini_set( 'display_errors', 0 );

This will generate a debug.log file inside the wp-content/ folder. Review this file to identify any PHP errors, especially those related to plugins.

Important: Once the issue is resolved, delete the debug.log file and remove the debug lines from wp-config.php to avoid security risks.

Resolving These Plugin Conflicts

Once you’ve reviewed the logs, you’ll likely see an error message like this:

Fatal error: Cannot redeclare hello_dolly_get_lyric() (previously declared in /wp-content/plugins/broken-plugin/index.php:17) in /wp-content/plugins/hello-dolly/hello.php on line 46

Here’s what that means:

Fatal error: A critical issue has stopped WordPress from functioning.
Cannot redeclare: Two plugins are trying to define the same function.
File path: The plugin and specific file where the conflict is happening.

To resolve it, use your FTP client or File Manager to navigate to /wp-content/plugins/, then rename the plugin folder that’s causing the issue (e.g., rename hello-dolly to broken-hello-dolly).

This tells WordPress the plugin no longer exists, and it will be deactivated automatically the next time you log in.

Avoid deleting the plugin unless necessary – you may need to investigate the code or settings further to understand the root cause.

For Developers: Good Practice Can Prevent A Plugin Conflict

If you’re developing custom plugins or themes for WordPress, following a few coding best practices can prevent conflicts like this from ever occurring:

Use unique function and class names. Prefix them with your plugin name to avoid name collisions (e.g., myplugin_custom_function()).
Wrap functions in function_exists() to check if they’ve already been declared.
Use class_exists() before declaring new classes.
Namespace your code if possible, especially in larger plugins.
Load your plugin’s features after others when possible, to avoid dependency issues.
Test your plugin in an environment that mirrors your live server setup.