How to create a Sender Policy Framework (SPF) Record to Authorise outMail Servers to send out your Email?
Although not essential it can help make email delivery more reliable if you create a SPF record for your domain name. This DNS record is to comply with the Sender Policy Framework (SPF) anti-spam initiative and it identifies outMail servers as being approved for sending emails from your domain.
It's a TXT record, which not all DNS servers or ISP control panels can handle, but if they can this is the record you need to add:-
example.com. IN TXT "v=spf1 include:spf.smtp-engine.com -all"
This is how it should appear in your DNS Zone File, including the inverted commas, but with your domain name substituted for example.com.
If you already have an SPF record, the key change required is to insert include:spf.smtp-engine.com before the -all, this will ensure that the outmail records are checked.