Procedure:

Step 01: In your control panel, click on Domains and then on the domain name in question.

Step 02: Now click on “Edit DNS zone records”.

Step 03: First, delete the default TXT record by clicking the Red X to the right on the respective row.

Step 04: Add the following SPF record to your DNS zone.

Step 05: Click Add record, pick TXT from the drop-down box, copy/paste the record into the Record Data field v=spf1 include:zcsend.net ~all