Some ISPs provide Listbox with a "feedback loop", or reports when list subscribers report messages as spam. When this happens, the subscriber who reported the message is immediately unsubscribed from your list.
If a subscriber did not wish to be unsubscribed, they can rejoin the list. However, please note that spam complaints affect your list's reputation, and you may find your messages blocked from other subscribers' inboxes. If a subscriber is repeatedly reporting your list messages as spam, getting unsubscribed, then rejoining the list, we recommend that you talk to your subscribers about why they may be doing so.
Some ISPs also automatically report messages that users' spam filters route to their Junk Mail or Spam folders. Those subscribers should adjust their spam filters to avoid having list messages caught by their spam filters. We recommend that list subscribers:
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