When a marketer sends their e-mail campaign to a list, they usually use software that takes the message and creates individual e-mails for each recipient. These individual messages are then queued up for delivery. For each recipient, the system must look up the domain and mail server. If, however, the domain look-up does not go through for a recipient, that e-mail is bounced.
If the domain look-up succeeds, the e-mail delivery program proceeds to connect to the recipient mail server. However, this is where another problem can occur. If the mail server is too busy, or if it does not approve of the way the e-mail delivery program is communicating, or if it possesses a list indicating that your system should not be communicated with, the connection will be broken and thus, the e-mail will be bounced.
Even if the connection is established, the potential for a bounce still exists. The e-mail delivery system must confirm that the intended recipient actually exists on that mail server and that he/she also has adequate disk space to accept the e-mail message. If either of these requirements is not met, the message will be bounced.
Though bounced e-mails do not get nearly as much press time as spam and phishing, it is still cause for concern for many mailers. According to a new study conducted by IronPort Systems, bounced e-mails cost senders about $5 billion each year. IronPort Systems is a gateway security company based in San Bruno, California.
The study also reports that bounced e-mails make up about 9% of all “hostile mail,” which includes spam, viruses, and phishing e-mails, and that only about 20% of all e-mail is legitimate. The remaining slices of the pie include 67% spam, 3% viruses, and less than 1% phishing attempts.
Patrick Peterson, IronPort’s chief technology officer, said he was very surprised to learn of the exorbitant cost of bounced e-mail messages. According to Peterson, marketers avoid talking about bounced e-mails and opt instead to discuss spam and phishing because “they don’t want to say millions of messages are bounced back.”
Sources:
http://www.clickz.com/experts/archives/
em_mkt/infra/article.php/996031
http://www.dmnews.com/cgi-bin/
artprevbot.cgi?article_id=36570
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