We have a daily report of accounts that seem defunct because emails to these users are being marked as “user not available”, which generally means that email account no longer exists on that particular email server.
The most common scenario, of course, is that someone has left their organization, but Kerika doesn’t know so that emails that are automatically generated are still being sent. An example would a user who used to get a 6AM Daily Summary email, and is no longer working at their organization: because she may have never explicitly asked for her account to be closed, or even turned off the 6AM Daily Summary emails, Kerika would have continued sending these to her.
We use our daily report of “bounced” accounts to determine whether we should delete them altogether as Kerika users or not. Each bounced account is examined individually to see if the user had logged in recently, or was working on boards owned by other (active) users. We err on the side of caution: if there’s any doubt we don’t delete the Kerika account.