The free version of Security Ninja works with WordPress.com, but Security Ninja Pro is not compatible with the hosted version of WordPress.com.
WordPress comes in two flavors – the version you can install and manage yourself for free (WordPress.org), or the hosted version on WordPress.com. The hosted version allows you to set up a website quickly and easily, without requiring technical knowledge. However, there are limitations to the plugins that WordPress.com allows to run on their system.
Security Ninja, by default, scans your entire website and needs deeper access to the filesystem than what is allowed on WordPress.com. Therefore, Security Ninja Pro is not compatible with WordPress.com, but it works seamlessly with WordPress.org, where you have full control over your site and its plugins.
