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<SGVFR-INSTRUCTORS@sgvfr.lan> (expanded from <instructors@sgvfr.com>): host
    sgvfr.lan[10.xx.xx.x] said: 550 5.1.1 <SGVFR-INSTRUCTORS@sgvfr.lan>:
    Recipient address rejected: User unknown in virtual mailbox table (in reply
    to RCPT TO command)


Reporting-MTA: dns; sparky.sgvfr.com
X-Postfix-Queue-ID: 67D7830044F42
X-Postfix-Sender: rfc822; dlloyd@sgvfr.com
Arrival-Date: Tue, 19 Mar 2019 10:21:15 -0700 (PDT)

Final-Recipient: rfc822; SGVFR-INSTRUCTORS@sgvfr.lan
Original-Recipient: rfc822;instructors@sgvfr.com
Action: failed
Status: 5.1.1
Remote-MTA: dns; sgvfr.lan
Diagnostic-Code: smtp; 550 5.1.1 <SGVFR-INSTRUCTORS@sgvfr.lan>: Recipient
    address rejected: User unknown in virtual mailbox table


test.eml
Subject:
test
From:
Dennis <dlloyd@sgvfr.com>
Date:
3/19/2019, 10:21
To:
instructors@sgvfr.com

test on Tbird using IMAP to instructors@sgvfr.com