Is there a way to determine whether an e-mail reaches its destination?

Question

I have a PHP script that sends out critical e-mails that needs to reach its destination. I know how to check whether the e-mail sent successfully, the only issue is knowing

Answer 1

There's no way to know for sure. Even if the remote server accepts the message, that doesn't guarantee it won't be filtered by a spam filter or otherwise.

Answer 2

If it's internal, send the email, but don't put the content of the message in the email. Provide a link to a web site and but an identifier in the url so that you can tie the page-view to the email.

You can still do that if it's external, as long as the people on the other end are cooperative.

You can also set up a vanilla account on the destination mail system and check that. If you get the email at that account, odds are the system is not set to filter it out.

You can also ask the admins of the receiving system to give you a bounce-back on well-received emails (you know, script that curls your acknowledgment web page), but that would require a lot of cooperation. Although at that point, it might be easier to deliver the message through a web service.

Answer 3

Why do you want to know that someone has read the mail?

Legally speaking, no way you might come up with will hold in court (say you want to make sure that someone has read an important document) because you can't prove that the reader was the recipient.

Security wise, your mail will be flagged by any decent spam filter as spam and deleted before anyone can see it because adding strange links or web bugs or images in a mail is just what the spammers do. And if you want to sell something, this is a surefire way to make sure you won't.

UPDATE: If you need to make sure people have read something, I suggest to send the mail with a link or a pointer to the document they should read. Don't add web bugs or personalized IDs to the link. In the document, tell them to sign the document and return a signed copy as proof that they have read it.

Answer 4

If I remember right as long as you send successfully, you can be assured that it has at least been accepted by the receiving mail server.

Answer 5

If you make the email HTML based, you can include images in it which contain URLs with information unique to the recipient. You could structure your application so that these URLs trigger some code to mark that particular email as read before returning the required image data.

To be totally effective, the images would have to form a key part of the email, so that the recipient has to make their email client grab the images. You could also make the plain text part of the email just contain a URL to retrieve the full message, again allowing you to track receipt.

How far you take these ideas depends on why you need to know it's been read and to what extent you want to potentially annoy the recipient with an email they can't cut'n'paste, read easily on mobile device, listen to with a screenreader, etc...

Answer 6

I guess all the above: images in the HTML, tracked links if they click on something. There are 3rd party services such as ReturnPath / Goodmail which can help.

The best advice is to ensure you're sending list is clean, IP address has a good reputation, reverse dns/spf records, good unsubscribe and bounce handling on the campaigns, spam check on content, and get recipients to add you to their address book.

That will give you a better chance of delivery...

Sundeep.//