How can I find out if an email has been delivered?

Question

Email

What methods can be used to find out if the sent email has been read? I know that they insert a picture and count the number of downloads, but this method does not give 100%, since pictures may not be shown. Are there alternatives? After all, postal mailing services provide complete statistics - read, hit spam, etc.

Answer 1

1. The main method of delivery control is tracking sending errors (bounce). The error is most often given directly to the SMTP session. In some cases, the recipient's server receives the message, but then generates a non-deliverable message (NDR).
By standards, issuing an undeliverable message to an SMTP session or sending an NDR is mandatory if your email is authorized (SPF and/or DKIM) - you can be sure that you will receive a bounce to the SMTP session or NDR if the email is not delivered almost 100%. Therefore, if a letter is not received within a reasonable time, it can be considered delivered. Undeliverable messages go to the sender address of the SMTP envelope (envelope-from). In order to know exactly which address which letter was not delivered to, you can create a unique envelope-from for each sent letter.
2. There is an SMTP extension called delivery status notification
https://tools.ietf.org/html/rfc3461
when sending a letter, you can request that the confirmation of the delivery of the letter to the mailbox or to the server of the recipient that does not support the DSN come in an explicit form. Confirmations are generated by the MTA without user intervention. It is not supported by everyone (for example, postfix does, Exim does not).
3. There is a non-standard Return-Receipt-To header, which works in much the same way as a DSN. But because it's non-standard, its support is extremely limited.
4. There is a standard (RFC 3798) Disposition-Notification-To header mentioned above, this is not a delivery notification, but a read notification. A request for this notification is usually shown to the user and requires their confirmation. Don't use this title unless you want to be cursed.
5. Pixel in the email - will not help to check the deliverability, but in some cases let you know that the email has been read.
6. (hello to the moderator). There are such services like postmaster.mail.ru and postmaster.yandex.ru , which allow you to track the deliverability of letters to recipients of these services, and this is about 70-80% of all recipients. In these services, you can view statistics on the delivery of messages, hitting the spam folder, actions with letters (read, marked as spam, deleted with/without reading). Moreover, you can set message categories through a special header or DKIM selectors and get statistics separately for message categories. This allows you to get information even on a separate letter by setting a separate category for it. But it's not worth it to do so.
This is the main source of data for spam hits / unread deletions, etc.
A bit off topic, but it might help:
7. You can (and should, if you organize mass mailings) set up trap boxes on different services, add them to mailing lists and track the deliverability of messages to these boxes, in particular, whether the letter got into the inbox.
8. Almost all major services support FBL . You can find out in real time if there are user complaints about your mailing list.

Answer 2

It seems that this has long been a standard feature - the delivery notification header: ("Disposition-Notification-To","[email protected]") - most modern mailers and mailing services support this feature.

Answer 3

You can shove a tracking pixel, with a link to your resource. There is an appeal to the pixel - the letter is read

Answer 4

There are standard email read flags that are supported by many email clients. However, this is not guaranteed, as not all clients implement auto-acknowledge, and usually the recipient must explicitly press the acknowledgement for it to go back.
Attaching active links to external resources is usually blocked by all adequate email clients, so any external pictures, etc. are blocked. - do not eat gud.
In short, no method can give a 100% guarantee that the letter has been read, and depending on the settings of the mail server, it is not even possible to give a 100% guarantee that the letter has reached the mailbox.
You can implement this only within the company, where you can set up automation. But again, a user can simply highlight a bunch of emails and mark them as read without actually reading them.