Net Q & A

Is there any way to determine if an e-mail has reached its destination other than to ask for a reply e-mail?

There are several ways to add, or try to add, the equivalent of a return receipt to Internet e-mail.

There are different types of return receipt:

Most mainstream e-mail programs (including Eudora, Netscape Messenger, MS Outlook Express and MS Outlook) have a "return receipt" feature built in.  For example, in MS Outlook 2000, in the message composition window, open the message to be sent, and select:

File | Properties | Return Receipt Requested

This will request a receipt for that particular message. To set general defaults for how your copy of Outlook will handle messages, from the main Outlook window, select menu choices:

Tools | Options | E-Mail Options | Tracking Options

The last menu gives multiple choices for automatically requesting "return receipts" and for managing return receipt requests from others. For example, you can set your software to automatically reject requests for return receipts, to automatically send return receipts, or to prompt you for a decision each time.

These methods are not perfect:

1. None will work unless the recipient is using a compatible client program and/or their ISP is using a compatible e-mail server. 

2. Some of these programs, give the recipient the option to refuse to provide a return receipt, thus limiting the value of the feature.   

3. Finally, because return receipts are not the norm on the Internet, some people might perceive requesting one to be rude, by implying that the recipient is unreliable or untrustworthy. 

Some of these methods are server-based (run on ISP's computer) while others are client-based (run on computers of senders and/or receivers). Some are based on proprietary protocols developed by e-mail software manufacturers, while others are based on Internet standards that have not yet been universally adopted. The only two Internet standards that I am aware of are: 

DSN is server-based. If your mail server and the recipient's mail server both support DSN, the return receipt feature will have your mail server send you a message indicating whether or not the mail was successfully delivered, i.e., a delivery verification receipt. Because it is server-based, it has no way of telling whether the message has been opened on the recipient's computer. 

If both ends support DSN, then you'll get a message back saying that the message was successfully delivered to the destination mailbox. If your server supports DSN but the other end does not, the return receipt will say only that the message was relayed to a non-DSN-aware mailer. If your server does not support it, you won't get anything back.

MDN provides message opened verification: It will indicate if the message has actually been opened, rather than merely if it was delivered to the mailbox. If the recipient does not have an MDN-compliant  mail program, there will be no receipt.

An alternative form of messaging is through vendor-operated web sites that hold messages until they are picked up by the recipient. This is not really "e-mail" as we know it, but it is another method of exchanging messages. The details vary, but generally, the sender uploads e-mail to a secure web site, which sends an e-mail notification to the recipient. Most of these sites focus on encryption as the big advantage of their approach (see, for example, Hushmail, Zixmail and Tumbleweed), with the return receipt being a bonus. CertifiedMail is a similar vendor that seems to emphasize the return receipt feature more than most.

This method has the advantage that the recipient need not be using the same specialized software. Nearly everyone already has web browser software installed.

Web bugs are a controversial do-it-yourself technique for e-mail tracking that I do not necessarily recommend, but will explain for the sake of completeness, and to alert those who do not want to be tracked so they can take defensive measures. This month's column is already pretty long, so I will save this discussion for the September Net Q & A.

Those who like to use web bugs prefer to call them by the less-sinister name "pixel tags." 

A web bug is a reference to a graphic image that is inserted into an e-mail message written in the language used on web pages, HTML. When the e-mail message is opened, it seeks out the image on the web site the author specified. By giving the graphic a unique name that is associated with that message, the owner of that web site can tell when the graphic is accessed.

It takes a little work, but not an extraordinarily high level of technical skill, to implant a "web bug" in an e-mail message. If you don't want to take the time or effort to learn to create web bugs, businesses like the Korea-based Postel Services will handle the details for you.

Web bugs are problematic, especially because they have great potential for abuse in a commercial context:

[P]rivacy advocates contend that such practices open a new window of surveillance on a traditionally private sphere of communications. They compare it to having someone who leaves a message on your answering machine — a telemarketer, say, or your mother — alerted the moment you listen to it. More troubling, they say, is that the same technology can be used to match a recipient's e-mail address with previously anonymous records of the Web sites visited from that person's computer.

Software to Track E-Mail Raises Privacy Concerns, NY Times, November 22, 2000. (Free registration required). 

Privacy Foundation Web Bug Regulation Proposal

Word Can Phone Home -- Jeff Beard explains how MS Word can be used to spy on users of Word documents, through the use of "web bugs."

Jerry Lawson