Self-destructing email is electronic mail that vanishes or becomes unreadable after a certain length of time or upon the request of the sender. Although self-destructing email technologies has existed for years, none has been very effective. Several new programs are said to offer better performance as well as email security and privacy enhancements.
There are two main types of self-destructing email. The first type, also known as retractable email, allows the sender to cancel or void a transmitted message as long as it has not yet been read by the intended recipient. The second type of self-destructing email theoretically disappears from the Internet altogether after a certain length of time has passed. The key word here is "theoretically" because if the recipient sees an email message preservation is always possible -- even if it means taking a photograph of the display screen on which the message appears or having multiple witnesses view the display in real time.
The most common method of creating a self-destructing message directs the recipient to visit a secure or encrypted Web site on which the message can be posted for a limited length of time. In order to gain access to the message contents, a password or decryption key is required. After the specified time limit has passed, the sender can delete the content from the site. However, once data has been written onto any magnetic hard disk, whether at the source, destination or any intermediate node, that data can be retrieved by someone with access to sophisticated data recovery technology even if it has been physically overwritten on the disk.
While self-destructing email technologies and programs will doubtless continue to improve, some experts insist that the best way to avoid criminal prosecution, civil litigation and other problems that can arise from inappropriate email is to give careful consideration to all messages before transmitting them. It is also a good idea to be sure that the email address of any intended recipient is spelled correctly so the contents do not end up in the wrong inbox. Wary experts go further and warn users against treating any form of electronic communications as if it were truly private, no matter what the provider may guarantee.