Bounced E-Mail Costs Mailers $5BIt may not get the same play as spam but bounced e-mail messages cost mailers a fortune, a new study found. E-mail senders lose $5 billion annually, and bounces make up 9 percent of all "hostile mail," a category that includes spam, viruses and phishing e-mails, according to the study conducted by gateway security company IronPort Systems.
IronPort, San Bruno, CA, examined global e-mail traffic using its SenderBase network and found that only 20 percent of e-mail is legitimate.
Spam makes up 67 percent of e-mail, misdirected bounce e-mails make up 9 percent, viruses consist of 3 percent of e-mail and phishing attacks are less than 1 percent.
Patrick Peterson, IronPort's chief technology officer, said he was "shocked" when he first heard about the cost of bounced messages.
"This affects the biggest brands and the biggest financial institutions, such as eBay and Bank of America, but it affects everyone," he said.
More than 50 percent of Fortune 500 corporations have experienced e-mail service outages or delays because of misdirected bounces that target their networks.
However, marketers do not talk as much about the bounced-message problem as spam or phishing because "they don't want to say millions of messages are bounced back," Mr. Peterson said.
Also, handling bounced messages is such a difficult problem for both e-mail senders and ISPs that they don't know how to handle it, he said.