I have the following problem with sending mail to one mailserver (domain) only!
When our mailserver is trying to connect to this domain, I'm getting this message:
550 5.7.1 Mail from xxx.xxx.xxx.xx refused.Rejected for bad WHOIS info on IP of your SMTP server
(where xxx.xxx.xxx.xx is our mailservers IP address)
Is this a blacklist? What to do now ?