Add "In-Reply-To" header on "Send Email" (SMTP) node

The idea is:

Add the headers “In-Reply-To” and “References” to Send Email (SMTP) node, to allow sending emails as replais to recieved emails.

My use case:

I want to reply an incoming email from n8n itself with an automated message. Now I just add "Re: " at the beggining of the subject, and mdoern email clients like Gmail treat this as a reply. But it is not the best way to do it, as it is very superficial. A better way to do it is to add the email ID (which is delivered to me on the Recieve email via IMAP node) at the “In-Reply-Tio” and “References” headers on SMTP, but this is not possible on the SMTP node on n8n.

Any resources to support this?

I’m also struggling with this. Did you find a solution @ruccc ?

Very interested in this. With the AI capabilities this is a must nowadays.

The Send Email node already has an option for reply-to, but not yet for references:

1 me gusta

Still no solution to set the In-Reply-To header so that a clean e-mail thread can be kept during conversations? :frowning:

There is already a PR for this (open since one year): feat: add in-reply-to and references to reply emails by jmrobles · Pull Request #9346 · n8n-io/n8n · GitHub

1 me gusta

I have made a custom node that allows you to add custom headers to SMTP emails.

https://www.npmjs.com/package/n8n-nodes-better-send-mail

The README includes instructions on replying to email threads.

1 me gusta

I also need to set the referrences header. the impact for n8n usage would be great. n8n should helps us automate stuff. unfortunately automating e-mail messaging is not possible in a good way with the existing nodes. the better-send-mail node is not available in the cloud hosting scenario, so that I cannot automate my e-mails. @n8n more automations means more transactions :wink:

I created a PR to add this feature: feat(EmailSend Node) Add In-Reply-To and References header support by martijngastkemper · Pull Request #38576 · n8n-io/n8n · GitHub. This works for my use case, but I’m curious to know whether it works for others as well.