SpamZa, which was taken down by its Web host late last month, asked site visitors to enter a valid e-mail address into its online form. Once entered, the site promised to subscribe that e-mail address to “hundreds” of newsletters and mailing lists: “Expect any e-mail entered in our form to receive 100-150 e-mails per day at the bare minimum, most being able to bypass most junk filters. To use our service, enter any e-mail and click ‘Spam this e-mail!’ and get ready to get spammed.”
Of course, if your e-mail newsletter requires a double opt-in, your list was probably safe. But those that weren’t are stuck with a corrupted list badly in need of cleaning. While it’s easy to say that marketers should simply switch over to a closed loop or double opt-in sign-up, that isn’t always possible, said George Bilbrey, president of Return Path’s Sender Score division, especially for those marketers that sell advertising in their e-mail marketing newsletters and charge based on CPM. But marketers do need to do something, he said, especially because SpamZa isn’t the first—and won’t be the last—mass e-mail spamming we’ll hear about.
“At least once a month we hear about someone who has written a script to pump a large amount of bad data into a form,” he said. “If you can’t do a closed-loop opt-in, you’ve got to protect yourself.”
Bilbrey suggested the following tips to help keep your e-mail list safe:
- Monitor where your opt-ins are coming from. If you look at your Web logs, you can see where opt-ins came from by looking at the originating IP addresses. If you see more than a few e-mail addresses that come from the same IP address, they may be fraudulent, Bilbrey said. “It’s not always the easiest thing to do, but it’s worth it for anyone who has easy access to their e-mail submission forms,” he said.
- Segment your list by length of subscription. Your oldest e-mail addresses are usually more valuable and safer, while new e-mail addresses should be viewed as risky, which is why they should be quarantined. “You might want to say, ‘The first five weeks I’m mailing to new addresses from this IP address. If it’s not causing problems after a few weeks, I’ll move that address,’ ” Bilbrey said. How do you make sure it’s not causing problems? Watch black lists and monitor spam complaints, he said.
- Look at new addresses carefully. Sometimes, spammers are so intent on causing problems that they get sloppy and submit e-mail addresses that are fake even to the casual eye. “Scan closely for addresses like ‘postmaster@,’ or ‘abuse@,’ or ‘post@’ or addresses with ‘spam’ or ‘trap’ in them,” Bilbrey said. “There are also some good commercial services that look for dead domains or addresses that don’t exist.” FreshAddress is one such service, while G-Lock Software is one company that provides software so you can do this on your own.
- Weed out nonresponders. If you’ve sent out newsletters for several weeks or months in a row—depending on your sending frequency—and a certain address hasn’t opened, clicked or converted, it’s probably not a good address and worth taking out completely. “Just stop mailing to them,” Bilbrey said. “Inactive addresses are often where spam traps live. You’ll keep off the spam traps without losing any economic value.”