This means that SpamCop found an email address to complain to, but it was invalid. If you find a more-correct place to report spam issues for the email in question, you may report these updates to firstname.lastname@example.org. Please do not send email unless you can provide a working abuse address where none was found before. You must confirm that the new address is correct and responsive to spam reports before you ask SpamCop to use it. We do not do the legwork of finding correct abuse email addresses.
Sometimes, if no correct contact information is on file, SpamCop guesses by using the RFC-822 required email address postmaster@ as well as the DNS server's administrative contact from the "SOA" record.
A good way to track down the correct abuse address is to visit the web page
of the domain that bounced your complaint.
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