Reclaim Bad Addresses — Carefully

As a professional e-mailer, you know conventional e-mail procedure dictates that whenever a message hard-bounces, you immediately remove the address associated with it and never use it again. Over time, that adds up to a lot of bad addresses and a lot of time and money spent acquiring them.

This may surprise you: all those addresses aren’t necessarily bad. If you review the error messages that accompany the bounces, you’ll likely find some bounces result from a temporary problem. If you can resolve the problem, you may be able to safely reclaim the address.

The error code, identified by a number and found in the text that accompanies each bounce message, specifies why a message couldn’t be delivered. Some messages hard-bounce due to irresolvable issues, such as a bad address or domain or a closed account. Others soft-bounce due to temporary account or technical issues. These error messages often contain a description (or link to the definition) that explains more fully why the e-mail bounced.

How do you know whether the e-mail message from a brand-new opt-in bounced because the address was bad or due to a blocking issue? Sometimes you don’t. The wisest course is to withdraw any hard-bouncing address from your active list before your next mailing. (Your list software should do that for you automatically.) But you don’t necessarily have to remove it permanently.

Some marketers are taking a radical step. They’re trying to reclaim as many addresses as they can by periodically e-mailing them and returning any good addresses to the main database. This is a bad idea. If you send to nonexistent addresses already identified to you by the ISP (true hard bounces) you can end up being blocked as a spammer.

Instead, remove bad addresses as usual and add them to a bad-address database. Be sure to keep the full error codes so you can inspect them for errors that aren’t the result of invalid accounts. Reclaim only addresses that resulted from a blocking issue that’s been resolved.

But beware: recovering bad addresses is like defusing a bomb. You must proceed carefully and identify the right addresses to reclaim, or risk blowing up your whole e-mail program.

What to Look For

Now that you have the list of hard bounces with the error codes, read past the 500-number reason code to the problem’s text description.

True hard bounces are messages that can’t be delivered because of irresolvable issues, such as:

  • Unknown user
  • Bad (misspelled) domain
  • Address error
  • Closed account

These are the addresses you must promptly remove from your active database. If you continue to send to them, the ISP will likely flag you as a spammer.

In contrast, here’s a sample error code for a hard bounce due to a blocking issue (e-mail address changed to protect the innocent):, Invalid Address, Final-Recipient: rfc822; Action: failed Status: 5.0.0 (permanent failure) Diagnostic-Code: smtp; 5.1.0 – Unknown address error 554-‘: (HVU:B1) 12TRANSACTION FAILED’ (delivery attempts: 0)

In this case, you can follow the URL to the ISP and attempt to resolve the blocking issue. Once you’ve resolved the block, you should be able to reclaim the e-mail address and send to it again. Notice the e-mail address is valid, but something else in the sending caused the bounce.

Test Only Resolved Addresses

The watchword here is “small.” Don’t try to save time by e-mailing to your entire bad-address database. Instead, create a sublist of only addresses with resolved sending problems.

Next, come up with your test message. This shouldn’t contain the same content you send to the active list. Create a lightweight text message to avoid potential HTML and preview-pane issues, indicate the problem and invite the recipient to update her address or unsubscribe. Remember, the recipient may not have heard from you in a while and may need to be reminded why she’s suddenly receiving e-mail from you again.

Send as usual, but watch sender logs carefully. Immediately dump all bounces. Return the good addresses to your database, but continue to watch sender logs.

Reduce Hard Bounces in the Beginning

  • Switch to a double opt-in subscription process, in which the subscriber has to reply to a confirmation e-mail before her address goes into your database. This is still the best way to avoid hard bounces based on misspelled user or domain names. It also helps reduce spam complaints and addition of spam-trap addresses to your list, the top reasons ISPs block senders.
  • Request a backup e-mail address, postal address, or phone number at registration. Contact your subscriber via an alternate channel if her address goes bad.

For further reading on hard and soft bounces and what those error codes mean, check out “Enhanced Mail System Status Codes.” Your overworked IT people will thank you for it, and you may actually understand what they’re talking about next time the subject comes up.

You invested a lot of time and money to acquire your e-mail addresses. Take a little more time to reclaim them the right way.

Keep on deliverin’!

Want more e-mail marketing information? ClickZ E-Mail Reference is an archive of all our e-mail columns, organized by topic.

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