I'm trying to implement List-unsubscribe. I have added a mailto: header but what's not clear to me is what e-mail is actually being sent when e.g. hotmail or gmail are sending an e-mail to this unsubscribe address.
Is it sending an e-mail with From: containing the e-mail address in question, or is it some hotmail/gmail service address?
Does anyone know a way to actually test it, since gmail and hotmail only activate this feature with highly trusted addresses (I've tried and it won't show).
This states:
- Include a List-Unsubscribe header
- Send an immediate confirmation message
I understand this as replying to the unsubscribe e-mail with a confirmation e-mail. Does anyone know if there should be any specific headers or contents in that message (e-mail)?
The unsubscribe should simply come from the address of the user who opted to unsubscribe. This is a very simple mechanism which should work with even extremely basic email clients.
The notation mailto:list-admin@example.net?subject=unsubscribe causes an email message with the Subject: header unsubscribe to be sent to list-admin@example.net.
There is an optional extension of the mailto: URI protocol specifier to allow you to put something in the body of the generated message, but this is less widely supported, and should not be relied on.
Maybe put a special unique identifier in the subject= field and set up the receiving server to handle that if these pedestrian facilities are insufficient for your needs.
If you are asking whether the confirmation message should follow any specific conventions, there's nothing beyond what you put in auto-generated confirmation messages in general. As a recipient, I would expect the unsubscribe confirmation to be pretty similar to the confirmation / welcome message when I originally signed up, only of course with the opposite contents.