On windows
Start
Run
Cmd
Ping SMTP.yourdomain.com (this will return an IP address x.x.x.x)
Enter machines IP in internet browser
Under SMTP settings input the SMTP ip x.x.x.x:21 or x.x.x.x:568 you got from cmd
Enter machine email address noreply@yourdomain.com
And done
Start
Run
Cmd
Ping SMTP.yourdomain.com (this will return an IP address x.x.x.x)
Enter machines IP in internet browser
Under SMTP settings input the SMTP ip x.x.x.x:21 or x.x.x.x:568 you got from cmd
Enter machine email address noreply@yourdomain.com
And done