Visual Editor is blank – 404 for plugin js

Have you updated to the latest version of the WCK – Custom Fields and Custom Post Types Creator plugin?

The issue is with the WCK – Custom Fields and Custom Post Types Creator plugin and you should probably seek direct assistance from them.

When I checked the plugins code (vers. 1.1.5) I can see in the wck-fep.php the reference to datepicker.css which may be causing the 404 error since it does not exist:

    wp_enqueue_style('jquery-style', plugins_url( '', dirname(__FILE__) ).'/assets/datepicker/datepicker.css');

They state in the Changelog that they fixed the issue with the 404 reporting for the datepicker.css in vers 1.1.0, but I still see code within the wck-fep.php file as mentioned above.

The changelog also states that in version 1.0.9 they changed from the tinymce to ckeditor plugin.

= 1.0.9 =
* Replaced wysiwyg editor from tinymce to ckeditor to fix compatibility issues with WordPress 3.9

    // wysiwyg              
    wp_register_script( 'wck-ckeditor', plugins_url( '', dirname(__FILE__) ).'/assets/js/ckeditor/ckeditor.js', array(), '1.0', true );     

Not certain why you’re still showing it still trying to access tinymce unless you’re using an older version of the plugin. I can not find any reference to it in the current version of the plugin.