Creating External Email Warning Banners


New Member
Nov 26, 2018
Hi everyone, quick question.

I'm trying to get Proxmox Mail Gateway to add an HTML external email warning banner to the top of the email body if the email is not received from a whitelisted domain, like this image:


I'm struggling on 2 things, how do append HTML to the top of the email body. I have tried using Disclaimer but I can only get that to add a banner to the bottom of the email.

Secondly, how can I tell PMG to add the banner if the TO domain IS NOT in the list? So far I can only get it to match if it is in the list...

Thanks guys! :)
Any news on this, im looking to edit the settings of the disclaimer so it appears at the top?
i am afraid both of those things are currently not possible with pmg
a disclaimer adds a text/html part at the end
and negate the matching of 'who' objects is also not really possible at the moment

you can of couse open enhancement requests here:
but i can make no promises that we will implement any of it
I also find this feature very important and think it's a shame that it hasn't been implemented yet.
Emails are one of the highest gateways that exist.

Currently, we manipulate the subject with [EXTERN], but even that doesn't work for the employees.

Is there already a solution, which I just haven't found yet?


Hi Imanudin,

Thank you for sharing the guide.

But if we need outbound Disclaimer and external Disclaimer, this guide will be always at the top.


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