Sender Policy Framework (SPF) Records are used for email validation to mitigate spam.
SPF records allow domain administrators to define all hosts allowed to send mail for a domain by creating a specific TXT record that is then used by mail exchangers to validate a senders identity. The data of an SPF record must be enclosed in quotations.
The original specifications for SPF required storage of SPF information for domains within TXT type records.
Later specifications created the SPF type record. Currently, there are no SPF implementation that will not use TXT type records if they are present, so SPF type records are not required.
There are, however, many SPF implementations that will not use SPF type records, so TXT records remain required. It is a good idea to have identical SPF information within a domain under both a TXT type record and an SPF type record.
SPF records can be generated using a free online tool from Microsoft located here.
When you add SPF information to your DNS records, you are able to specify the email servers you use to send email from your domain. This validates your sending email address, which can improve your email deliverability rate. In other words, SPF helps to keep your domain’s email out of your recipients’ spam folders.
To get started, you must first contact your DNS hosting company and ask them to add the following SPF information to your DNS records. Or, if you can log into the control panel for your DNS, you can make this change yourself.
v=spf1 [any combination of the below] ~all
Hosted Exchange and Email Hosting customers:
If you send email from your own server (replace “184.108.40.206” with your mail server IP):
For example, if your domain falls into both of these categories, the SPF would look like the following:
v=spf1 include:emailsrvr.com ip4:220.127.116.11 ~all
Repeat these steps for every domain from which you plan to send email.
Note: When you are composing an email, you must use a “From” address (or, specifically, a “Return-Path”) that belongs to an SPF-enabled domain, otherwise SPF will not be in effect.