The importance of data hygiene

Over the weekend, one of the major ISPs purged a lot of abandoned accounts from their system. This has resulted in a massive increase in 550 user unknown bounces at that ISP. This ISP is one of those that uses bounces to feed into their reputation system and the purge may cause otherwise good senders to be blocked temporarily.
Talking to clients and other industry folks, it looks like the addresses that have newly bounced off had zero activity for at least 6 months. Nothing. Nada. No clicks. No opens. No interaction.
This is why data hygiene is so critical. Just because the emails are being accepted at the ISP, and even showing inbox placement at the mailbox monitoring companies does not mean that there is actually someone reading your email. Failure to look at overall data means that when an ISP bulk deletes abandoned accounts then bounces will increase. While I don’t expect this to have any real, long term effect on sender reputation I do expect that some senders with a lot of cruft on their list will see some short term delivery problems.
Companies that run re-engagement campaigns saw a whole lot less bouncing and even less blocking as a result of the purge. They were removing addresses that were non-responsive all along and thus didn’t have major deadwood on their list.
Ongoing data hygiene shows you what your list really is, not your list plus abandoned accounts. The addresses that the ISP purged? They were not valuable anyway. No one was reading that mail for at least 6 months.
If you did see a spike in bounces this weekend at a major ISP, you should really look at engagement. If some percentage of recipients at one ISP are actually non-existent, then it’s likely that about that same number are non-existent at other major ISPs as well. What are you going to do to identify and remove those dead addresses from your lists?

Related Posts

AOL transmitting 4xx error for user unknown

AOL is currently returning “451 4.3.0 <invaliduser@aol.com>: Temporary lookup failure” in some cases when they really mean “550 user unknown.” This message from AOL should be treated as 5xx failure and the message should not be retried (if at all possible) and the failure should be counted as a hard bounce for list management purposes.
This is something broken at AOL’s end, and the guys with the magic fingers that keep the system running are working to fix it. Right now there doesn’t seem to be an ETA on a fix, though.
Even if you are a sender who is able to stop the retries, you may see some congestion and delays when sending to AOL for the time being. Senders who don’t get the message, or who are unable to stop their MTAs from retrying 4xx mail will continue to attempt delivery of these messages until their servers time out. This may cause congestion for everyone and a noticeable  slowdown on the AOL MTAs.
AOL blog post on the issue
HT: Annalivia

Read More

Delivery resources

I’m working on a few projects designed to help provide mentoring for other delivery people and to bridge the communication gap between the various groups active in email. One of those projects is collecting, linking to, and publishing more delivery resources. Some will be linked to directly from the blog, others will be linked to from the wiki. While I’m reasonably familiar with what’s out there, it is impossible for me to know about all the useful resources available. So I ask you readers:

Read More

Protecting customer data

There have been a number of reports recently about customer lists leaking out through ESPs. In one case, the ESP attributed the leak to an outside hack. In other cases, the ESPs and companies involved have kept the information very quiet and not told anyone that data was leaked. People do notice, though, when they use single use addresses or tagged addresses and know to whom each address was submitted. Data security is not something that can be glossed over and ignored.
Most of the cases I am aware of have actually been inside jobs. Data has been stolen either by employees or by subcontractors that had access to it and then sold to spammers. There are steps that companies can take to prevent leaks and identify the source when or if they do happen.

Read More