Sender Policy Framework – An authentication protocol used by recipient sites to verify that the originating IP address is authorized to send email for the domain name declared in the “MAIL FROM” line of the mail envelope. SPF is used to identify messages with forged “MAIL FROM” addresses.
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The 3 Things To Avoid When Emailing Your List
When you decide to have an opt-in list, it is not just a matter of sending your subscribers your promotional newsletters or catalogs.