How to Create an SPF record to stop spammers sending from your domain

Easiest way is to use the tool at http://www.openspf.org to generate the syntax for the SPF record.

If using Windows DNS server add a new TXT record for your domain and copy and paste the generated record removing the quotation marks.

What is SPF?

SPF is an extension to Internet e-mail. It prevents unauthorized people from forging your e-mail address. For it to work, your own or your e-mail service provider’s setup may need to be adjusted.

Otherwise, the system may mistake you for an unauthorized sender.

There is no central institution that enforces SPF. If a message of yours gets blocked due to SPF, this is because (1) your domain has declared an SPF policy that forbids you to send through the mail server through which you sent the message, and (2) the recipient’s mail server detected this and blocked the message.