Sometimes, while trying to open the Divi → Theme Builder and edit any template parts (Header, Custom Body, or Footer layout), an error alerts the user that an unknown error has occurred. Please try again later.
Possible causes
Outdated Divi Version
Outdated WordPress version
Outdated PHP version
Values of server's PHP directives to low
Plugin or Child theme conflicts
Outdated Divi Version
Make sure that you are running the latest Divi version. You can check that by going to Appearance → Themes, clicking on Divi theme, and checking the version number.
If you have a correct API Key and username set in Divi → Theme Options → Updates Tab, you will be able to update Divi to the latest version directly from there.
Outdated WordPress version
Ensure that the website is running on the latest WordPress version.
From the Dashboard → Updates tab, you can check for the WordPress version and reinstall the latest version.
Outdated PHP version and/or low PHP Directives values
Both can be checked if they are met by going to the Divi → Support Center and checking the System Status report to make sure everything is in the green:
If there are any red dots, we recommend checking with the hosting support team to address any of those.
Plugin and/or Child theme conflicts
Usually, 3rd party plugins could create unwanted issues that might prevent Divi from working properly.
Checking for such conflicts is easy, thanks to Divi's Safe Mode feature.
The Safe Mode can be enabled from the Divi → Support Center.
With the Safe Mode enabled, we can check again if loading and editing Theme Builder templates works as expected.
Note: While the Safe Mode is enabled, the following items will be disabled.
3rd Party plugins
Child theme (in case one is used)
Custom code (CSS and JS)
This will only happen for the currently logged-in user who has activated the Safe Mode and will not impact the website's visitors.
If Safe Mode resolves the issue.
With Safe Mode enabled, try loading the Divi Theme Builder. If the error has been fixed, we must determine which plugin caused it.
Go to WordPress Dashboard → Plugins → Active Plugins tab;
Click on Active tab
Use the checkbox to select all active plugins
From the dropdown, choose Deactivate
Click on the Apply button
With all the plugins deactivated, try again to edit your page or the Theme Builder template
If it works, return to the Plugins page → Recently Active tab and activate one plugin at a time.
After each plugin activation, check again if the issue has been solved
If Safe Mode doesn't resolve the issue
In case when Safe Mode doesn't resolve the issue, we can check other possible causes:
WordPress Permalinks
Incorrect protocol
WordPress Permalinks
Check if the error is gone while using the WordPress Plain Permalinks.
To change the Permalinks, go to WordPress Dashboard → Settings → Permalinks.
Usually, the Permalinks are set to Post Name. After switching the Permalinks to Plain, check if the error has been fixed again.
If the error has been fixed while using the Plain Permalinks, the hosting support team will require further investigation.
Incorrect protocol
If the website is using an SSL certificate, make sure that in WordPress Dashboard → Settings → General, the correct HTTPS protocols are being used for both URLs:
WordPress Address (URL)
Site Address (URL)
If the SSL certificate was installed after the WordPress was installed to the server and content (pages, posts, products, etc.) were already published, installing a 3rd party plugin called Really Simple SSL will also help in fixing Protocol errors, which might lead to Divi Builder Timeout error.
Edge Cases
In some cases, the issue could be related to the content of the template part we are trying to edit:
Header layout
Custom Body Layout
Footer Layout
This could happen when custom HTML or CSS code is used in those template parts. However, there are syntax errors.
Since editing those template parts is no longer possible, you can try to rebuild them from scratch using an unassigned template.
Create an unassigned template.
Head to Divi → Theme Builder and create a new template.
In the Assignments window, don't check anything;
Click the Create Template button.
This will create a new template that will not be assigned to anything, allowing you to recreate the template part that cannot be edited.
Once the template part is recreated, you can delete the faulty one and copy over the recreated one.