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<administrator@localhost>: Host or domain name not found. Name service error
   for name=localhost type=A: Host not found

Final-Recipient: rfc822; administrator@localhost
Original-Recipient: rfc822;administrator@localhost
Action: failed
Status: 5.4.4
Diagnostic-Code: X-Postfix; Host or domain name not found. Name service error
   for name=localhost type=A: Host not found