Em@ilCRX (EmailCRX) is a desktop based, automated e-mail filtering software system that uses reverse DNS validation, country filtering, user defined phrases, and a challenge response system to stop spam from making it into your e-mail inbox. Effective e-mail filtering without the errors possible with content, or RBL based filters. Em@ilCRX will collect all of the e-mail from all of your POP e-mail account(s), and using its reverse DNS based e-mail Rating Engine system, Country Filter, user defined phrases supported by Regular Expressions, and Challenge Response system, Em@ilCRX will validate the e-mail, letting through only the e-mail that is in a user managed friends list, or passes validation, or receives a valid challenge response. Valid challenge responses will automatically add the e-mail address(es) of the responder to the user's friends list. The user retrieves messages cleared by Em@ilCRX using their e-mail client software (e.g. Apple Mail, Outlook, etc...). Cleared messages can also be forwarded to your handheld device (Blackberry, etc.). Spam can be reported with the click of a button.