Generic Error Notification in Setup
Generic Error Notification in Setup>Notifications>Object Type: Note
Currently, the "Error Notification" - "An error was found that needs your attention" is being used for the POP Email disabled notification.
After many (150) failures to connect to POP email, we will disable the email in order to stop constantly checking a bad email in order to preserve resources. when this happens we send an email to the project owner (if email was on a Request Queue) or the System Administrators (if email failures were on the Allow reply... note reply setup). It was, apparently generically named due to the possibility of using it for other future error notifications.

But currently, it's only governing POP email errors, and only when it reaches the threshold of failures where we disable the POP account.