The short answer here, dear Heathen, is that absolutely NONE of these will EVER work in a reliable way on the open Internet. It’s possible, within some corporate email systems (Exchange, Notes) to do this, but that’s because those servers and clients all speak the same proprietary language. On the Internet, you have to play by the global standard rules, and most mail servers see no reason to honor the requests of mail senders to edit, remove, expire, or otherwise molest emails — largely because once you hit send and the mail finds its way to our mailbox, we consider it OURS, not YOURS, and our systems aren’t interested in deleting our stuff on your say-so.
This is the right answer. This is the way these things SHOULD work. Anything else is a security nightmare and shady besides.
We took a look at one such system today: BigString. Note their initials; it’s prophetic. They claim to be able to “un-send” a message, delete a message after the fact, set expiration/auto-deletion dates, track how often a message is read, and a myriad of other things that, in all honesty, cannot be done with Internet email. Curious, we signed up to see how it worked.
As expected, they’re doing this by:
- Turning your email text into a graphic;
- Hosting that graphic on their server;
- Sending a mail message that references, but does not enclose, that graphic.
At this point, you’re reading a web page, not an email. This means that non-graphic-friendly email clients (Windows Mobile, perhaps Treos and Blackberries, etc) won’t be able to read the mail at all, and people with sane security settings on their desktops will have to adjust their mail configuration before they can see anything. That’s charming, right? Anyway, while they claim they can keep recipients from saving or printing these messages, we had no trouble at all dragging the graphic to our desktop to save for later, printing the file, or forwarding the graphic to someone else. (Also, they’re treading into the same dodgy territory as DidTheyReadIt and their ilk, covered previously.)
It’s just not possible to control, and here’s why: your computer has to make a copy of the file to show it to you. You’re not reading it off their server. You’re reading it locally, and once you have it locally, it’s beyond their control.
Put not your trust in these foolish things. Be careful what you put in a mail, and forget giving bozos like BS time or money. Email is as it always was, and attempts to make it jump through hoops like this are doomed to failure.
(Oh, another thing about Big String: it took them nearly and hour to deliver my test message to me, and test messages sent to my test account at BS have yet to arrive, more than an hour later. This suggests they may have bigger issues than a snake-oil product.)