Email Authentication
Email authentication is the effort to equip messages of the email transport system with enough verifiable information so that recipients can recognize the nature of each incoming message automatically. Enabling email authentication will help fight the spread of spam.
Both of the methods below work to prevent forged mail from going in and out of your server. The great benefit of enabling these methods is to prevent mail from looking like it is coming from your domain(s). When enabled, these methods should reduce the amount of bounce messages or unwanted emails received when spammers "spoof" one or more of your email addresses.
DomainKeys
DomainKeys is an e-mail authentication system that allows for incoming mail to be checked against the server it was sent from to verify that the mail has not been modified. This ensures that messages are actually coming from the listed sender and allows abusive messages to be tracked with more ease.
SPF
SPF will specify which machines are authorized to send email from your domain(s). This means that only mail sent through this server will appear as valid mail from your domain(s) when the SPF records are checked.
If you have multiple domains under your account on the same web server the above settings should work for all email addresses.
To see if Email Authentication and SPF are enabled on your web hosting account, please login to your cPanel.
Under the Mail menu, click on Email Authentication.
