[Zawifi-lista] Undelivered Mail Returned to Sender

This is the Spam & Virus Firewall at tsrbrc01.bpn.pt. I'm sorry to inform you that the message below could not be delivered. When delivery was attempted, the following error was returned. <[email protected]>: host 192.168.13.98[192.168.13.98] said: 550 5.1.1 User unknown (in reply to RCPT TO command)