This is the mail system at host srv15.ffnw.de.
I'm sorry to have to inform you that your message could not
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The mail system
<core@freifunk-ol.de>: host srv01.ffnw.de[37.120.176.207] said: 550 5.1.1
<core@freifunk-ol.de>: Recipient address rejected: User unknown in virtual
mailbox table (in reply to RCPT TO command)