-CONFIRM or -RC command adds a special tag to email header. This causes most of the email clients to ask for confirmation that message is received. Some email software might be configured to automatically send confirmation replies.
Note that even if reading confirmation is received, it does not actually guarantee that email is read by user. It is possible that reading confirmation was generated automatically by mail client.
C:\>febootimail -SERVER smtp.server.com -FROM firstname.lastname@example.org -TO email@example.com -TEXT "Requesting confirmation" -CONFIRM
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