DUAL Softswitch sends a number of emails to your customers automatically, including a welcome email for new accounts; rate change notifications and low balance warnings. These emails are sent from your support email address.
There is a chance that some of these emails will not be delivered, because your customers' email servers may not expect to see emails from your email domain arriving from our mail server. Some mail servers check the valid source of emails using SPF (Sender Policy Frameword) as a method of blocking spam. The domain name administrator can specify the valid sources of emails from their domain by adding an SPF record to their domain's DNS entries.
If you are the administrator of your email's domain name, then you can authorise emails from our mail server by creating an SPF record. An example would be:
"v=spf1 mx:dualsoftswitch.com mx ~all"
This record would allow emails sent from your domain's existing mail servers and also from the mail server handling emails for our domain dualsoftswitch.com.
If you use another company's email service, such as gmail or hotmail, then you will have no control over their DNS entries, and you may not be able to avoid email delivery failures.