home *** CD-ROM | disk | FTP | other *** search
- ###########################################################################
- # [Reject invalid To: header]
- #
- # Description: "Reject email where the domain name in the To: is invalid"
- # Keywords: "headers, To:, rejection methods, domain name, hostnames"
- # Category: "Junk mail detection"
- # Format: "{TRUE OR FALSE}"
- #
- # Reject any mail where the To: header appears to be invalid.
- #
- # The To: header is the portion of an email message, which is read by the
- # recipient, which looks like this:
- #
- # > To: "Jane Somebody" <jane@money4u.com>
- #
- # If the email address specified in the To: header does not have a domain
- # name, or if the domain name specified does not appear in the Internet DNS
- # records, then the To: is considered invalid.
- #
- # For example, this to:
- #
- # > To: friend@public.com
- #
- # specifies the "public.com" domain, which is not a real domain, and so
- # MailShield detects this and rejects the message.
- #
- # A common technique with junk mail is to put an invalid email address in
- # the To: header so that the recipient of the email message cannot respond,
- # nor can they determine who the message was really to. Internet mail
- # standards require that some sort of correctly formatted email address be
- # in the To: header. MailShield takes this requirement further, actually
- # checking to ensure that the To: points to a real domain name, as well as
- # performing other, more stringent syntax checks.
- #
- # Note that MailShield only tests the domain name. If the domain is valid,
- # but the email address isn't a real user for that domain, i.e.
- # <xyz12345@juno.com>, then it will not be rejected based on this test.
- # However, it may be rejected by one of the other configuration options.
- #
- # Mail with just a user name, such as "bob" will be considered invalid by
- # this option. Junk mail sometimes comes addressed like this, so that it
- # appears to be coming from a local user. MailShield, however, knows when
- # mail is being sent from a local machine (and therefore, a local user is
- # acceptable) by the hostname or TCP/IP address of the machine, which is
- # defined in the MailShield configuration. In this way, only mail sent from
- # local hosts can be addressed From: a local user, and any mail from outside
- # your domain may not be.
- #
- # We recommend that this feature be enabled.
- #
- # By default, this setting is enabled.
- #
- # Instructions: "Please enter the word TRUE or the word FALSE below."
- FALSE
-