Document information

Document ID:4663
Subject:Resolved IP in HELO string does not match with Sender IP
Creation date:12/14/15 4:35 PM
Last modified on:8/13/18 10:52 AM

Resolved IP in HELO string does not match with Sender IP


Some emails are being rejected for the following reason.
Resolved IP in HELO string does not match with Sender IP


When a sender SMTP server connects to your email server, it sends a HELO string, which looks like:

Among other email etiquettes, the domain name present in the HELO command should match with the sender's IP address. For example, if an email originates from the host name should resolve to this IP. If it resolves to a different IP address, Xeams is going to assign a score to this message.

Most legitimate email servers will use a matching host name in the HELO command. If you see a good email getting this score, consider letting the sender know that their email server is not configured correctly.

User comments

Posted by Muhammad Waseem Khan on 7/31/18 5:56 AM

Please 550 Resolved IP of HELO argument didn't matched. Kindly clear this DNS IP Thanks and Regards, Waseem Khan

Posted by dcol on 6/7/16 6:12 PM

I find this is a common occurrence with local email. To fix, just add the local LAN to the whitelist. ie 192.168.1.*

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