What do you do if you have a large volume of your customer database which has no email address alongside it, or has an email address that is no longer valid?
You obviously want to find up to date email addresses for these customers and the most popular (cheap) way of doing this, is to use an email append service.
This seemingly innocent process has taken a bit of flack recently, first being soundly thrashed by the Messaging Anti Abuse Working Group (MAAWG for short) and then very publically pilloried by Experian Cheetahmail.
So what has caused this to happen? And what should you consider before embarking on an email append project?