WordPress Plugin Conflicts: How to Check for Them and What to Do

When you think about the potential problems plugins can cause for your WordPress site, you probably think about poorly coded plugins that lead to performance issues and security vulnerabilities, right? Or maybe you’ve read something recently about fake plugins and now are worried about the authenticity of your plugins and the security issues those could lead to.

But there’s one other plugin-related concern you should be aware of as you add new plugins to your site or even as you update existing plugins:

Plugin conflicts.

It’s awesome that there are tens of thousands of plugins made by different developers, all created with the intention of serving different purposes. That said, there is nothing that guarantees that what one developer has created won’t conflict with something else on your site. These conflicts usually come about as a result of:

A conflict between two plugins.
A conflict between your theme and a new or updated plugin.
A conflict between a plugin and your site’s current WordPress version.

Symptoms of a plugin conflict typically occur in one of two forms. Either your site starts acting wonky–specifically, a plugin stops acting the way it’s supposed to–or the white screen of death rears its ugly head after the last update or latest install of a new plugin.

If this has happened to one of your WordPress sites, you need to know how to troubleshoot and take action quickly to remedy the situation. The following guide will provide you with the steps you need to take in order to identify a WordPress plugin conflict and then consequently fix your site. I’ve also included tips on how to avoid these conflicts in the future.

Continue reading, or jump ahead using these links:

How to Troubleshoot and Fix WordPress Plugin Conflicts
How to Avoid WordPress Plugin Conflicts in the Future

How to Troubleshoot and Fix WordPress Plugin Conflicts

There’s a good reason why WordPress and other plugin repositories provide so many details, technical specifications, customer reviews, and more for each plugin or theme listed. It’s because they expect users to review this information to make an informed decision about which plugins they allow on their websites. This is especially helpful for users who aren’t capable of inspecting the code, but want to know if there are any potential issues to be aware of.

In the above example, you can see that each plugin page gives users ample opportunity to make sure the developer keeps their plugin updated alongside WordPress. Users also have the chance to see what others have said about the plugin in the Ratings and Reviews as well as to see what sort of issues they’ve experienced under Support.

It’s this last one where you’re bound to discover known plugin conflict issues before they’ve had a chance to touch your site.

Let’s say, however, there haven’t been any publicly reported issues with plugin conflicts. What do you do if a plugin stops working, an error message shows up on your site, or you see the white screen of death? Here are the three most common scenarios you’re likely to find yourself in and what to do about them:

Scenario 1: Site Is Up, but Plugin Isn’t Working

If one of your plugins isn’t working correctly or at all on your website, but you still have access to WordPress and your site, check if an update is available. Something about the CSS or JavaScript within it may have suddenly set off the problem (I’ll talk about that more below).

Follow your usual process for issuing plugin updates. Then check your website. If the issue resolved, then the plugin developer was aware of the conflict or general issue and fixed it.

Scenario 2: Updated Plugin or Installed New One, Now Something’s Broken

Whether you’ve just added a new plugin to your WordPress site or you’ve updated one (and only one), it’s easy to identify the source of a busted website. No troubleshooting should be needed.

Simply deactivate the suspected plugin and return to your site. Does everything look okay? If so, then you’ll want to report the issue to the plugin developer so they can issue a fix. While you wait for that to happen, work on finding a replacement for the plugin or scour your favorite WordPress blog to find hand-picked suggestions for one.

Scenario 3: Automated or Batch Updates Made, All Hell Has Broken Loose

Don’t get me wrong: I don’t think there is anything wrong with automating core, theme, and plugin updates in WordPress. In fact, I think it’s a smart business move since streamlining and automation are the key drivers to success. However, if you do automate your updates in WordPress, do know that resolving plugin conflicts will take a bit more work.

There are two different paths you will have to take, depending on how the error presents itself on the website:

When Your Plugin or Theme Breaks, or Error Message Displays at the Top
Your site is still up and running (thank goodness) and you can access WordPress. Good. Here is what you need to do if something breaks on your site in this manner:

1. Check your most recent backup. If it’s from right before the update was made, restore it. Then skip down to #5.

2. If you don’t have a recent backup saved, go into WordPress and deactivate every single one of your plugins.

3. Check your website to see if the problem has been resolved. If so, then your issue is a plugin.

4. Switch your theme to the default WordPress theme.

A theme update can sometimes be at fault if the developer added new functionality that mirrors functionality in a plugin you’re already using, so it’s important to rule this out. Check your website again to make sure the problem is gone. If the problem is still there, then your theme is at fault and you’ll need to contact the developer about the problem and find a replacement theme in the meantime.

5. If the problem has been resolved with the theme switch, then it’s time to test each of your plugins one by one.

6. Start by reactivating your primary plugin, if you have one. This will be the case if you have a specialized website for e-commerce, hospitality, memberships, etc. Confirm that your site remains problem-free with this one plugin activated.

7. Next, add the plugin that you suspect to be the issue. If your site was showing an error message, it should tell you the actual name of the problematic plugin. If not, start with the one that’s not working.

8. You’ll need to do this for each of your plugins until you find the one creating the conflict. Be sure to deactivate the one you just vetted before activating the next one. This will cut down on the number of variables you have to consider in terms of where the conflict exists.

9. Once you’ve found the plugin conflict, deactivate it and report the issue to the developer in the repository or with their support team if it’s a premium plugin.

10. It’s then up to you to decide whether to roll the plugin back to a previous version (which I wouldn’t recommend since you’ll continue to run into this issue and you should always use the most up-to-date version of the core, plugins, and themes), to get a replacement plugin, or to do without that feature completely.

When You See the White Screen of Death… Ugh!
The white screen of death is a scary prospect for every WordPress user. However, if the source of it comes from a recent update batch, then the solution is a quick one to implement:

1. If you see the white screen of death, you won’t be able to access WordPress which means you can’t get into your plugins. In this case, go to your control panel and use SFTP to access your site’s files.

2. Deactivate all plugins. You can do this by renaming your “Plugins” folder to something else.

3. If you’d rather just delete all the files (which will also deactivate them), save a backup of them somewhere else first. Once they’ve been deleted from the folder, you can re-upload the saved plugins to that same folder. This will not reactivate them, it’ll simply put them back on your server.

4. By deactivating your plugins, you should now be able to log back into WordPress and follow the process described above as if you had WordPress access from the get-go. If you still see the white screen of death and have cleared your cache, the theme is the guilty party.

5. To deactivate the theme, do the same as you would your plugins: change the “Theme” folder name or delete and re-upload the theme file to the folder. You should then be able to return to WordPress and switch your theme.

How to Avoid WordPress Plugin Conflicts in the Future

As you can see, WordPress plugin conflicts aren’t too difficult to clean up. It just requires a little patience and some time to identify the source of the problem. The fix is an easy enough one to execute once the troubleshooting work is done.

That said, time is money. While it may be easy enough to resolve these types of WordPress issues, why put yourself in that position if you don’t have to? You could spend it instead on building more websites or improving your business processes.

If you’d like to avoid this hassle altogether, here are some tips you can add to your process to help you (and your clients) avoid WordPress plugin conflicts in the future:

In general, WordPress plugins should not be downloaded and installed on a whim. The less plugins you use, the less likely you’ll be to run into trouble. So, choose your plugins wisely.
Always take the time to read plugin reviews and support tickets before installing and activating a new plugin. If you’re short on time, then use recommendations from a trusted third-party or blog to get you moving with one.
Keep plugins updated at all times.
Update plugins one at a time so you’ll more easily identify which is the troublemaker (even if that’s not the most efficient way of handling updates).
If you use an automated updating tool, make sure it runs a backup first and uses safe upgrade technology…like Automate.
Check in on your plugin set every few months. If you encounter any that have lost developer support and updates for more than six months, find a new one.
Back up everything before you make any updates or install new plugins.
Use a local testing environment to duplicate your live site. This way, you can test new plugins or updates for potential conflicts before pushing them through on your WordPress site.
Brush up on the WordPress Codex’s coding standards guidelines. Even if you’re not developing plugins or themes for your sites, it still might be worth knowing what makes for good coding practices if you want to inspect plugins before using them.
Also, take some time to familiarize yourself with hooks. Often, plugin (and theme) conflicts come about when developers don’t give their hooks a unique name. By using the default, they run the risk of using a hook that another plugin or theme uses, which, in turn, confuses the server and generates the conflict error.
Brush up your HTML, PHP, and JavaScript skills. If you become frustrated with the number of conflicting plugins out there, you can always code this functionality into your website and avoid that issue in the future.

Wrapping Up

Of course, there is one more way to be smart about activating and using plugins on your WordPress site. Rather than collect an SEO plugin from this developer over here, a speed optimization plugin from this developer over there, and an analytics plugin from yet another developer, why not just get all the essentials from a single, trusted provider?

WPMU DEV has a fantastic collection of WordPress plugins that will cover pretty much all your needs for developing stunningly powerful websites. And if you decide that you need an outside plugin to cover an obscure need, you can always ask the support team about whether or not they’re aware of known conflicts. It’s as easy as that!