Webmail sending with browser IP instead of Server (relay reject issue)

Support WebMail
1

We have a bunch of remote users using webmail, and they can send within the domain fine, but when the try to reply to an external email, a Relay Reject is logged, as it appears to reject based on their (remote) IP. (firewall port forward from outside, only on 443).

How do I configure Axigen to use the mail Server’s (internal local LAN IP) for webmail sending source instead of the user’s browsers?

2

Hello Bill,

For all messages the server is adding a Received header that includes the IP address of the device used for sending the message. For normal mail clients it will be the IP address of the PC or mobile device.

Now, for messages sent from WebMail interface the server will add the IP address of device on which the web browser is running (PC or mobile device) and the header will looks like:

Received: from [78.99.55.222] by mail.domain.com with HTTP; Thu, 2 Dec 2021 21:08:02 +0000

There are cases when the receiving party will scan all Received headers in an attempt to reject possible spam as much as possible. Unfortunatelly, the IP addresses of some of your remote users may be on some blacklisted ranges and the only think you may do is to remove the WebMail specific Received header so there will be no evidences of their IP addresses used when sendim those messages.

There is no simple switch for this and you have to create an advanced routing rule via WebAdmin > Security & Filtering > Acceptance & Routing > Advance Settings > ADD new rule:

  • name: webmail-hide-ip
  • enable rule: checked
  • conditions: ALL
    ** Remote address > EHLO host is: <enter-here-your-server-ehlo-host>
    ** Connection > Is Authenticated: checked
  • actions: Headers > Remove first header: Custom: Received

where <enter-here-your-server-ehlo-host> is, obviously, your server EHLO host string and could be checked into the PROCESSING logs for WebMail sent messages, like below:

2021-12-02 21:03:34 +0000 16 test-001 PROCESSING:0030D06A: << EHLO mail.domain.com

and, usually, is the hostname of your server (if you didn’t change as mentioned in this KB)

Please ley us know if above rule is working for you (meaning there will be no Received header containing with HTTP text into messages sent via WebMail interface,

HTH,
Ioan