The preview HTML did not include a closing </html> message and Cornerstone POST error

[n3ilxb9394]

Hello,

I am receiving this error when opening the editor, going to content, and clicking edit on a page.

I applied the solution to alter my functions.php with :
add_filter( ‘w3tc_can_print_comment’, ‘__return_false’ );

That hides the error, but the content editor still won’t work. I have errors in my console that say:
POST http://<mysite.com>/cornerstone-endpoint 500 (Internal Server Error)

Followed by:

Please advise why I can not edit ANY pages in the content editor. I can provide login info to my site if needed.

[christopher]

Hi there,

I suggest that you follow the troubleshooting steps below:

1. Ensure everything is up to date according to our version compatibility list here. Please follow the best practices when updating your theme and plugins. Click here for more information.
2. If you’re using a CDN, please clear the CDN’s cache and disable optimization services.
3. Test for a plugin conflict. You can do this by deactivating all third-party plugins, and see if the problem remains. If it’s fixed, you’ll know a plugin caused the problem, and you can narrow down which one by reactivating them one at a time.
4. Remove custom CSS and Javascript from the options or Child Theme and test the case.
5. Increase the PHP Memory Limit of your server. Click here for more detailed information and how to increase the PHP memory limit.
6. Follow the steps mentioned in this article.
7. I see that the error is from cs-vendor.js I am not sure if it can be related but read this article and contact your hosting service provider.

If you still have problems kindly get back to us with the URL/User/Pass of your WordPress dashboard using the Secure Note functionality of the post to follow up the case.

Thank you.