Summary / TL:DR: This article will show you how to permanently unsubscribe a customer from an eletter in Advantage.

Use these instructions when a customer would like to never be able to resubscribe to an e-letter.  When a customer is in status I, B or S for Inactive, if they resubscribe to the list - either by making a purchase or signing up through a link on a website - their status will be set back to A.  Once their status is set to X, they can no longer sign up to the list unless contacting customer service directly.

This should be used only in cases where a customer is irate and specifically requests to not ever receive emails from a list.  For general unsubscribe requests, go here.