Another way to prevent repeat incoming unwanted email, is to block an individual email address. Once you're logged in to your cPanel, click on 'Mail' from the menu, and choose the Email Filtering' function. From that screen, you'll be able to view your filters and set new ones with the link at the bottom which will help to control inbound mail to your account. You may wish to block mail by:

 - Sender
 - Subject
 - Message Header
 - Message Body

Please be careful when using the feature to make sure you don't block legitimate or all your email by mistake. Also, please do not use special characters (hash, star, hyphen, etc, etc) in the blocking rules as these are likely to break your email.