we have recently moved office and servers and now I get the following from a remote mail server when we try and email a user there.
mx7.freeparking.co.uk gave this error:
"E5:Mail rejected because 18.104.22.168 doesnt have valid Reverse DNS."
When I run a DNS check at: http://www.intodns.com/letterpart.com
It's coming back showing that my Reverse PTR is ok.
Your reverse (PTR) record:
22.214.171.124.in-addr.arpa -> mail.letterpart.com
You have reverse (PTR) records for all your IPs, that is a good thing.
Now. 126.96.36.199 is the IP address of the Exchange server but 188.8.131.52 is the gateway it sends through and what all tests, pings and sites show as the IP my server is sending from.
When I originally had 184.108.40.206 as the Reverse PTR. All the tests I ran showed it as failing so we had it changed to 220.127.116.11
Why is this one mail server complaining about my PTR while everyone else is happy and do I need to have 18.104.22.168 added as well to make it happy?