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SMTP Masquerading denied when using unknown domain

  • Hi,

    I configured nodeBB with the cloudron mail relay and the relayed-to server is within an internal network directly attached.

    It seems that emails are denied by cloudron's relay when the From/Reply-To address nodeBB uses is from a domain that is not but rather from
    I want to use this noreply on my second level domain because the "discard" functionality is already configured there.

    The nodebb log looks like this; There is no request being logged on the relayed-to mailserver.

     error: Mail command failed: 550 Authenticated user cannot send mail as {"code":"EENVELOPE","response":"550 Authenticated user cannot send mail as","responseCode":550,"command":"MAIL FROM"}