How to Troubleshoot an Ineffective E-Mail Campaign

A bouncing e-mail is not too dissimilar to a bouncing check. When you bounce a check it means that there were insufficient funds for the check to go through, and when you bounce an e-mail it means that there was insufficient positive information for the e-mail to go through.

Just like bouncing a $10 check at the corner shop is going to cost you $40 in NSF charges from your bank, as well as another $25 (+ embarrassment) from the store, the negative ramifications of bouncing an e-mail are disproportionate to the violation committed.

Bounce too many e-mails and your entire reputation will be tarnished: You'll find it increasingly difficult to get your e-mails campaigns delivered. Just like you'll find it difficult for anyone in town to take your check.

Soft Bounces vs. Hard Bounces

There are two types of bounces, and while one is relatively innocuous, the other will have the effect of a whole checkbook made out of rubber.

Soft Bounces -- These can be summed up as bounces that really aren't your fault. These occur when you send an e-mail to a valid address but you receive back messages such as:

• Mailbox quota exceeded
• Out of office autoreply
• Temporary local problem
• Too many sessions

These messages indicate that there is a transient problem preventing delivery, but in most cases these e-mails should be deliverable later on that day or the next. Soft bounces are not usually something you should worry about, however receiving repeated notices that the recipient's mailbox is overflowing can indicate that the e-mail address is no longer in active use and should be purged.

Hard Bounces -- These ones are the big red NSF stamp of the e-mail world. You'll receive a notice stating something along the lines of:

• Incorrect domain
• Mailbox no longer active
• Mailbox not found
• Unknown user

These bounces are "mostly" your fault since it's generally acknowledged that you should be current with the recipient's e-mail address status. Buckshot sending to a whole bunch of dead addresses is a key identifier of spamming.

Interpreting The Errors

The error messages can contain clues as to how you can remedy at least some of the problems and clean up your list:

Incorrect or unknown domain: This usually indicates that you've mistyped the domain name, but in some cases ISPs will change name and stop supporting the old one.

Mailbox unavailable: Sometimes this can mean that the mailbox is dead, while other times it can mean it's only sleeping. You can try contacting the recipient through an alternate e-mail address if you have one.

Unable to relay: This generally means that somewhere along the line in the transfer of your message one of the ISPs thought your message was spam. Not much you can do here.

Listed in or blocked: This is the really bad one: One of the blacklisting services like spamcop or blackhole has determined that you belong in the V1@gR@ set. Completely revamp your message to ensure you don't have any red flag content or structures in your e-mails, which are triggering the filters.

Don't Overrule The Daemon

Read your error messages carefully as sometimes the system will continue to try to send your message with no further action on your part. It's not a good idea to overrule the mailer daemon and resend the e-mail directly, as that might convince the filters that you're spamming.

Consider bounces as undesirable as returned checks and do everything you can to avoid repeated bounces. Your reputation with both blacklist filters and shop owners will benefit.