Did you run into a “spam trap” before?

Spam busters sometimes try to sneak inactive or incorrect e-mail addresses onto mailing lists on purpose, in order to verify if the sender use best practices for mailings. How do those “spam traps” get onto your mailing lists and which is the best way to respond to them?

It probably already happened to you that, when sending a mailing to your customers, your e-mails got labelled as spam by automatic filters. Despite the fact that you are not doing anything wrong. The people you address with your e-mails indeed confirmed that they wish to receive your messages. This “spam” label is determined by automatic filters that are used by most providers and anti-spam services (e.g. SpamAssassin, SpamCop, SpamHouse, URIBL…), based on different signals.

Like we explained before, an untidy arrangement of the mail’s HTML code and the use of colours in the text make up one signal. Another signal is the use of certain “suspect” words or URLs in the mail (words with a sexual connotation, brands of certain male enhancement products, web addresses of sites that have a reputation of spreading malware). Another important signal you certainly must not ignore is your reaction to what is called a “spam trap”.

What is a “spam trap”? It is a booby-trap of sorts – a fake e-mail address that is used to check who is illegally collecting e-mail addresses or who does not use the correct procedure when handling addresses for mailing lists. Because, if you do not respond in the right manner by removing the trap address from your list after a mail bounced, the e-mail address from which your mailing was sent will be considered a spammer.

How does such a fake address get into your address file? Generally, when you import addresses without checking them. They can be addresses you get from address books you collected over the years; certain addresses may have been cancelled by their users after a while, before being activated as a spam trap by the provider. Spam filters therefore think it is strange that you are sending an e-mail to an address that is not active and thus cannot have subscribed (through opt-in) to your newsletter.

They can also be bulk addresses that you purchase or haphazardly collect – and it is especially there that you must pay attention, because those databases are often crammed with invalid, old, cancelled e-mail addresses… and spam traps.

Moreover, such a wrong address can also be present in your mailing list unbeknownst to you and slumber there for a while because your mail provider or mailing script do not send you an alert the way they should when the message could not be delivered. And if you do not receive a report, you are of course unable to remove the address from your file.

Another possibility is that you gather addresses by letting people fill out forms offline. And even when filling out a form online, users may – inadvertently or on purpose – provide an invalid e-mail address.

How to avoid spam-traps? Steer clear of address lists that you can purchase somewhere cheap. Collect addresses yourself through an opt-in system. And work with a double confirmation: after subscription to your newsletter, send a welcome e-mail containing a button that the user has to click to confirm that he indeed wants to subscribe to your mailing list. Only after having received this confirmation will the address be definitively added to your mailing list. That way, you are certain that you are dealing with a real e-mail address, because a spam trap is not able to reply to the confirmation e-mail.

This double confirmation is a little bit more complicated, but at least you are certain that you are working with a clean list of addresses. Also, check if your mail provider or mailing script sends clear reports when e-mails bounce. For instance, create a fake e-mail address and check if you receive a delivery failure notice for the message that was refused to this address.

Also, react immediately when e-mails come back undeliverable and remove the subscriber from your listing. Do not wait for weeks, because you will get a bad rating from spam filters. For that matter, it is a very clever strategy to follow up if your e-mails are indeed opened; if you have subscribers who have not opened any of your e-mails in the past 6 to 12 months, try to reactivate them with cleverly written mails. If they do not react, just remove their address. This is how your mailing list remains up-to-date.

Remember: as the old saying goes “A bird in the hand is better than two in the bush”. A mailing list of 500 addresses that regularly open your messages is much better than a list of 5000 addresses of which only 100 really read your messages, which can, on top of that, give you a bad reputation with spam filters!