I have just experienced, for the fifth time, a silent-but-deadly problem with email delivery systems. I wrote about it back in 2005, but recent experience shows another discussion of the issue is due.

Have you found there are companies from whom you cannot get email? No matter how many times you go to their site and sign up, the email never gets to your inbox or even your junk mail filter. The problem is likely a business rule that put your email address on the unsubscribe list. With most email systems, this is the court of last resort -- a final filter before the mail is sent. Once you are in the unsub file, you are suppressed from all future mailings.

Often the reason and date of the action that put you in the unsub file is not captured. As a result, a subsequent resubscribe won't do any good. The unsubs are suppressed against the subscribers, period.

This problem is created when companies clean their subscriber lists and put their inactives in the unsub file. It's particularly dangerous if you have made assumptions about the subscriber's interest. If you're wrong and they do try to resubscribe, they'll never get your publication.

Another reason a subscriber may end up in the unsub file is an unacceptable number of bounces. If the bounce reason is cleared up, or if the bounce rules are deemed too strict for the program, the subscriber is still left in the "permanently out" category.

The biggest problem with this issue is that it is often unnoticed. Pay attention; see how many subscribers you lose between the initial list pull and the sent file. If the number is alarming (I've seen up to 30%!), have an IT staffer look into the reasons.

Good Luck!

The Email Diva

Send your questions or submit your email for critique to Melinda Krueger, the Email Diva, at emaildiva@kd-i.com. All submissions may be published; please indicate if you would like your name or company name withheld.

This commentary is insightful. I recommend it to others.