How do legitimate e-mailers correct a ‘black hole’ listing?

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Answer: “Black hole” lists are basically databases run by individuals or corporations concerned with fighting unsolicited bulk e-mail. Mail servers that are identified as sending spam can be reported and listed, and Internet service providers (ISPs) or corporations can subscribe to these lists to help reduce spam to their customers. A mail server appearing on such a list can thus have its e-mail messages blocked or quarantined, hence the nickname “black hole.”

Being placed on a black hole list is relatively easy in today’s recipient-focused e-mail client environment. There are several black hole lists out there, and an ISP can subscribe to one or all of them, if it wishes. If enough people make a complaint against a server, the typical reaction is to report the server to a black hole list. If you find a sudden increase in bounced e-mail, hard or soft, or a corresponding drop in open and click-through rates, it could be the result of the mail server being placed on a black hole list.

Other reasons e-mail servers get reported are: poor bounce management, not honoring unsubscribe requests and bad sending habits, such as sending e-mail blasts too frequently or not sending what was promised. All of these issues can cause recipients to point their mouse to the “report as spam” button in their e-mail client. If these underlying issues are never addressed, there will be ongoing appeals to the spam reports, and the server will endlessly be listed in one place or another. Often when a server is blocked, it affects other IP addresses in the same range. This is one of the main reasons ISPs are so restrictive. They cannot afford to have any of their servers blocked because of one person’s bad behavior.

When a spike in the bounce rate occurs, it’s a good idea to try to capture a bounced message or two. A professional e-mail marketing solution worth its weight usually has a debug feature that, when enabled, archives the conversation with the bounce account and logs the reason for the bounce in a tracepop.log. Another investigation option is to copy all bounced e-mail messages and forward them to a separate e-mail account, just long enough to identify in more detail the reason they bounced. You can also quickly reference black hole list check tools such as or Email Tools Blacklist check.

Typically, when there is a bounced e-mail message related to a black hole listing, the message will provide you with a link to the list. This link can explain why the server is listed. Many of the black hole lists have procedures to help an e-mailer easily remove a server from their list, mostly involving providing proof that you really are not spamming. Subscription dates, e-mail policies or other data may be required before a computer can be successfully removed. There is also an expectation—and maybe a requirement—that whatever caused the problem in the first place be addressed.

Black hole lists themselves are typically not the problem, but a result of some underlying problem in your e-mail marketing campaign. Black hole lists actually help to raise the consciousness of legitimate bulk e-mail marketers everywhere, encouraging them to higher standards. Certainly spammers will not take appropriate steps to get back in the good graces of a black hole server; they simply set up a new domain in a new area until they are inexorably caught again.

If you find that your server has made it on a list, don’t panic. Examine your e-mail behavior carefully and correct the underlying reasons that you were put there in the first place. Then contact the list managers and work with them to get the server delisted.

Jim Kinkade is the technical support supervisor at Arial Software (, a provider of performance e-mail marketing software solution.

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