How to reject fake messages from your Subscribers (using SPF)
Traditionally, mailing lists processed emails from subscribers without regard to the origin of the message.
These days, with increasing amounts of spam and malware being sent with spoofed email addresses, it is prudent to verify the origin of the email.
SPF (Sender Policy Framework)
SPF (Sender Policy Framework) allows all domains to declare what IP addresses their emails will be sent from. These settings are made in DNS, by each domain.
Mail-List.com can read these SPF settings before releasing any message to your mailing list
If the subscriber has defined the SPF settings to reject any email, not from their pre-approved IP addresses, we will send the email to the moderator for approval.
Not all of your subscribers or their domains have defined their SPF settings
If your subscriber has not defined their SPF settings, there is nothing for Mail-List.com to verify the origin of the email against. Therefore, all email messages will be sent to your mailing list, including fake emails.