Late last year, Comcast blocked the IPs of one of Pivotal Veracity’s clients, preventing them from being able to deliver any email. We contacted Comcast on behalf of the client to inquire why they were being blocked and learned that Comcast’s filter (Brightmail) reported a significant portion of this client’s mail as spam. We got Comcast to remove the block, but when the client mailed their entire house file again, they triggered Comcast’s filters again. Pivotal Veracity again had the block lifted but, as you can imagine, something had to be done.

The mailer’s first tactic was to only email subscribers with any post-signup activity such as clicks or purchases regardless of how long ago. Unfortunately, this also resulted in Comcast blocking the mail. The implication: Just because someone was engaged at one time, does not mean they are still engaged and, as many folks do, they used the “report spam” button to get off the list.

After having their last three campaigns blocked, the mailer, rather desperate now, decided to test emailing only to Comcast addresses that had made a purchase—a dramatic measure but one with dramatic results. This strategy has consistently yielded 100% inbox delivery. In the case of this mailer, their older, inactive users were complaining which caused all emails to be blocked by Comcast. Emailing “less” was the difference between $0 and generating a return on investment from their Comcast subscribers, which are a significant portion of their file.

This real-world example is further proof that marketers need to actively manage their email lists to prevent them from going stale. To help you, the eec Deliverability & Rendering Roundtable has written “How to Revive a Stale Email List,” a reportlet that lays out step-by-step how to salvage stale lists and actively prune lists before too many inactives build up. The reportlet, which is available in the eec’s Whitepaper Room, also discusses why you should avoid “soft touch” services. Does anyone else have any stale list horror stories?

—eec Deliverability & Rendering Roundtable chair Michelle Eichner of Pivotal Veracity