WordPress customizer crashes after installing MC4WP plugin

Plugin Contributor


What theme are you using?
What version number of MC4WP plugin are you using that came with your theme?

When the customizer stopped working, what happened? Did you get a white screen, or an error, or something else?

Thanks for letting me know.

@lapzor, Thanks for responding.

I’m using “Blonwe” theme which I bought from Themeforest. I’m not sure about the version number, but I’m 100% sure it’s latest version because I don’t have any pending updates in my WordPress site.

After activating the plugin, when I open WordPress customizer, the left side menus are working, but live preview is not showing at right side. The browser tab head is showing “Customizer: Loading…”. The preview page is blank. Sometimes I get error as “There has been a critical error on this website”.

  • This reply was modified 2 hours, 48 minutes ago by wellshot. Reason: Added info

Plugin Contributor


Under Plugins > Installed plugins you can see the version number.

If the MC4WP plugin came with your theme you can also try to uninstall it and do a fresh install of the MC4WP plugin from the WordPress repository.

My guess is that the theme you use has some custom MC4WP integration that is causing the issue, so if you just recently bought the theme and still have support with it I recommend you contact the theme author about this as well.

I guess the version number doesn’t matter here. Because as I don’t have any pending updates, so, I can assume that I have the latest version installed which you released.

If I uninstall the plugin, I will lose the demo data and the subscription form that came with the theme. So, after that, installing the plugin again doesn’t make any sense to me.

The weird thing is I’m encountering the issue after entering MailChimp API key. Before that, I was ignoring the plugin and it didn’t bother me.

Yes I bought the plugin a month ago.

Plugin Contributor


Hopefully the theme support will be able to help you as I highly suspect it’s custom code that comes with your theme that causes the issue.

If for some reason they can’t or won’t help you I really need to know the version number you’re on. Reinstalling the plugin won’t make you lose any data.

Kind regards,


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