Setting Up Support for Sender Policy Framework System

To set up support for Sender Policy Framework on your server:

  1. Go to Home > Mail Server Settings (in the Server group). The server-wide mail preferences screen will open on the Preferences tab.
  2. Select the Switch on SPF spam protection check box and specify how to deal with e-mail:
  3. To specify additional rules that are applied by the spam filter before the SPF check is actually done by the mail server, type the rules you need in the SPF local rules box.

    We recommend that you add a rule for checking messages against the open database of trusted senders, for example, 'include:spf.trusted-forwarder.org'. For more information on SPF rules, visit http://tools.ietf.org/html/rfc4408.

  4. To specify the rules that are applied to domains that do not publish SPF records, type the rules into the SPF guess rules box.

    For example: v=spf1 +a/24 +mx/24 +ptr ?all

  5. To specify an arbitrary error notice that is returned to the SMTP sender when a message is rejected, type it into the SPF explanation text box.

    If no value is specified, the default text will be used as a notification.

  6. To complete the setup, click OK.