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                   The mail system

<ia.comune.casnateconbernate-RwE6Ndc99cFLGcBWcxgnif9lYrnsuH/l@public.gmane.org>: host
    10.11.49.139[10.11.49.139] said: 550 5.1.1
    <ia.comune.casnateconbernate-RwE6Ndc99cFLGcBWcxgnif9lYrnsuH/l@public.gmane.org>: Recipient address
    rejected: User unknown in virtual mailbox table (in reply to RCPT TO
    command)