newsletter mailboxes

To receive the bounced messages generated by sending newsletters and mass mailings,
you need to setup additional mailboxes (e.g. bounce@…)

and optionally one mailbox for receiving reply emails (e.g. news@…)
if you want to filter them and send automatic replies to the most common requests.

For this reason we introduced two mailboxes matched to your RealSender account:
bounce@email.youremaildomain.com -> bounce@rsXXX-realsender.com
news@email.youremaildomain.com -> news@rsXXX-realsender.com

Explanation:

Using a Mail-From address (also known as bounce/return-path/envelope address)  
with a domain other than the From address
would break the DMARC authentication

To use the "newsletter mailboxes" 
you need to set up a sub-domain of the From address

e.g.  the From address is:           offers@youremaildomain.com
      the sub-domain could be:       email.youremaildomain.com   CNAME   rsXXX-realsender.com
      the Mail-From address becomes: bounce@email.youremaildomain.com

The suggested configuration follows the rules
to send DMARC compliant emails on behalf of customers.

DMARC allows you to send authenticated emails using a sub-domain (such as email.youremaildomain.com), and still be able to use the top-level domain in the From: header (e.g. From: offers@youremaildomain.com).

No additional settings are required in the DNS of your domain name.

As per RFC1912 section 2.4:
 A CNAME record is not allowed to coexist with any other data.  
 In other words, if email.youremaildomain.com is an alias for rsXXX-realsender.com, 
 you can't also have an MX record for email.youremaildomain.com, or an A record, 
 or even a TXT record 

The mailboxes have been configured so that they can receive
large amounts of emails in a short time, as in the case of bounces.
!!! Please note: email messages are automatically deleted after 7 days !!!

To download the emails, you should configure your email client,
or the application that analyzes the bounced messages,
with the following POP3 server address: pop.rsXXX-realsender.com.
Usernames and passwords are available through the website’s restricted area.