The preview could not load due to the iframe response being incomplete. Can't find the error!

[olefischer89]

Hi,

I’ve read a bit about this error here in the forum but I am not able to fix it. I had already contact with my host provider (Bluehost), the updated some memory settings and checked other things but nothing works.
The complete error message is (when clicking on “customize pro in theme options” and the for example on “assign a menu”):
The preview could not load due to the iframe response being incomplete. This is most often related to a plugin conflict, or customizations introducing a PHP error.

It would be great if you could help me!

Cheers,
Ole

[ruenel]

Hey Ole,

Thanks for writing in!

" The preview could not load due to the iframe response being incomplete. This is most often related to a plugin conflict, or customizations introducing a PHP error."

The error above shows that there is a fatal PHP error which stopped the rendering of the website and you need to follow the steps below:

• Enable the WordPress debug mode. You might be able to see an error message on the site right away. If not, the error log could reveal where the problem is originating.
• If you’re using a child theme, try switching to the parent theme to see if that makes a difference. The conflict could be in your customizations.
• Test for a plugin conflict by disabling all third party plugins except the Cornerstone plugin if you use X. IF the problem is fixed, activate the plugins one by one to find the plugin responsible for the problem.
• Make sure that you use PHP version 5.6.x or 7.1.x or 7.2.x. Contact your hosting service provider to make sure that you do not have an old version of the PHP.
• Make sure that you increase the PHP memory limit to at least 512M. Follow the steps mentioned here for more information.

And if nothing is helping, provide us access to your site so that we can check your settings. Please create a secure note with the following info:
– Link to your site
– WordPress Admin username / password
​
To know how to create a secure note, please check this out: https://theme.co/docs/getting-support

Regards.

[olefischer89]

Hi,

thanks for the response. I’ve tried everything but nothing worked.
It would be great if you could have a look on it.

Thanks a lot!

[ruenel]

Hello Ole,

Thanks for providing the information. I have logged in and check your site. Everything seems to be working as expected. I created a test page and it loads in the Pro Editor.

see the secure note for the test page.

Kindly clear your browser cache or you private browsing mode and then test your site again.