I've been trying to resolve an issue with SenderBase reporting a client's IP as a "poor" rating for a while; which has been causing massive problems trying to communicate with a major business . I resoved issued with reverse DNS, etc. but the last step was ensureing any device that initiated or responded to SMTP reported the correct EHLO/HELO.
As soon as I configured both the Endian SMTP Proxy and Exchange Server to the same string, mail stopped flowing with the following error;
postfix/smtpd[4539]: NOQUEUE: reject: RCPT from xxxxxxx.xxxxx.xx[.xx..xx]: 450 4.1.1 <
xxxxxxx@xxxx..xx>: Recipient address rejected: undeliverable address: mail for [192.168.73.2] loops back to myself; from=<
xxxxxxx@xxxxxxxx..xx> to=<
xxxxxxx@xxxx..xx> proto=ESMTP helo=<xxxxxxx.xxxxxx..xx>
Can anyone offer any assistance with this one??
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