Tuesday, April 26, 2011

New Setting: Preserving the original Message-ID header in transactional email

We've added a new checkbox on the Settings --> SMTP Relay page, that allows you to preserve the Message-ID of an email sent via the SMTP relay, rather than have it be overwritten by the JangoSMTP system Message-ID, which is the default behavior.

The JangoSMTP system Message-ID looks like:

Message-ID: <254970262215471@jngomktg.net>

It's a unique number followed by @jngomktg.net. Some JangoSMTP users have asked that the original Message-ID of the message transmitted through the relay be used instead of being overwritten by the JangoSMTP system Message-ID. For example, if you send an email using Mozilla Thunderbird, the Thunderbird-generated Message-ID looks like:

Message-ID: <4DB66014.1070804@silicomm.com>

In Thunderbird's case, the Message-ID contains a unique string of alphanumeric characters and uses the domain of the receiving email address. If the Preserve Message-ID box is checked, this will also be the Message-ID in the final email delivered to the recipient. If unchecked, this Message-ID will be replaced by the JangoSMTP system generated Message-ID.

Calling the API directly

If calling the transactional email API directly via the SendTransactionalEmail method, you can specify a custom Message-ID in the Options parameter using the CustomHeaders attribute:



Why is this useful?

Allowing you full control of the Message-ID header value is useful if you have a custom reply management system in place, such that responses and bounces can be tagged with their original Message-ID.