External relay change email "from" address to junk

[yasanthau]

Hi,

We configured the Zimbra server (V 8.8.11) to relay emails through external relay service "Mailgun". Followed similar commands shown in this guide. https://mangolassi.it/topic/17808/zimbr ... -rackspace

Out going emails are sent with an abnormal from address such as "bounce+49b856.976cdf-recipient=domain.com@domain.com". This makes emails to be detected as spam by recipient mail servers. When asked from Maingun, they say that it is normal and nothing to worry. Some recipient domains accept the emails and some not. Is there any setting from Zimbra side which does not allow Mailgun not to change email headers? Any support in this regard is highly appreciated.

Thanks,

Yasantha

[phoenix]

Why do you find it necessary to send your mail through a relay? Can't you send the mail directly or could you use your ISP's servers to relay mail? FWIW, the relay host can do whatever it likes when you relay mail through them and once it's left your ZCS server there's nothing much you can do.

[yasanthau]

Hi,

Thanks for the response. We had to migrate our email server from a cloud service provider to Digital Ocean. They do not allow port 25 (out going) as a policy. We did not know it before the migration. They recommended to use third party relay services such as Sendgrid and Mailgun. We selected Mailgun. Zimbra server should be configured to send out going mails through this authenticated relay service. It is something similar to this https://wiki.zimbra.com/wiki/Outgoing_S ... entication

Now from address is shown as "bounce+49b856.976cdf-recipient=domain.com@domain.com" for some recipients. This can be seen in all out going mail headers. Mailgun does not provide a solution for this. I just want to know whether we can restrict this through Zimbra.

Thanks,

Yasantha

[phoenix]

This can be seen in all out going mail headers. Mailgun does not provide a solution for this. I just want to know whether we can restrict this through Zimbra.

I've already answered this above. Once the email has left your server teher's nothing you can do to stop another server adding headers, it will do that for traceability and there really should be no problem with those headers.