Problem: Hotmail cannot deliver mail to certain domains: "Relay Access Denied"

Problem: Hotmail cannot deliver mail to certain domains: "Relay Access Denied"

The error message is:

Diagnostic-Code: smtp;554 5.7.1 <user@domain.com>: Relay access denied

Solution:
When there exists an A record in DNS for a specific domain, on certain occasions hotmail.com tries to deliver mail to the server at the IP address the A record resolves to. This is the case when there is (another) e-mail server running on that IP-address.
This is wrong because it only should try to deliver mail to the MX records in your DNS server and not to the A records.

The easy solution here is to just delete all A records. But then your web server will be unreachable!

The harder solution is to follow the instructions I have learned here on windowslivehelp.com

The only fix (short of getting MS to do something) is to convince the person who runs the domain you are trying to email to (hilariously) block hotmail's IP's from sending mail to there web server.


I did this for my linux mail server with the following;

iptables -A INPUT -s 65.52.0.0/14 -p tcp -j REJECT --reject-with icmp-port-unreachable

Note: you may have to add more IP's to this range, I am unsure if msn, live, etc use other IP's

Cheers!