Denis Yanchevskiy

Allows you to make post, page, custom post elements required: title, content, featured image.
After installing the plugin, you need to go to the Settings -> DCO Post Validator to specify the required elements.

DCO Post Validator

Allows you to make post, page, custom post elements required: title, content, featured image.

Germain-Italic

This is a simple plugin which is designed to help the posters who sometimes forget to write the post content (main editing zone). Once activated, this plugin will force the users to give post content while adding new post to WordPress site. Whenever User tries to publish a post without giving content, it will give an alert to the user and also highlight the content area so that user can see where to write the post content. I have tested this plugin with WordPress 3.5.1 and it works fine. It should work with older versions of WordPress also.

Force Post Content

A simple plugin to force user to write Post content in Add Post page. Based on Jatinder Pal Singh’s ”Force Post Title” plugin.

DCO Post Validator vs Force Post Content