Hello I have a user that some of their emails are returning .....
A message that you sent could not be delivered to one or more of its recipients. This is a permanent error. The following address(es) failed:
host xxx.xxx.xxx.xxx [xx.xx.xx.xx]
SMTP error from remote mail server after MAIL FROM :<*****@*****.COM SIZE=5685: 550 5.1.0 <***@***.com> Supsect mailer domain please check your DNS records - ERR007
Any direction on where to start with this error?