Undelivered Mail Returned to Sender

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This is an automated message from the BorderWare Security Platform
at host CNLB.GOV.AB.CA.

The message returned below could not be delivered to its 
intended
destinations.

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Reason:

<harn@xxxxxxxxx>: host 142.229.229.10[142.229.229.10] said: 550 5.1.1 User
    unknown (in reply to RCPT TO command)

Reporting-MTA: dns; CNLB.GOV.AB.CA
X-BorderWare-Security-Platform-Queue-ID: 7524190B3C18BC70
X-BorderWare-Security-Platform-Sender: rfc822; kernprof@oss.sgi.com
Arrival-Date: Sun, 20 Apr 2008 07:17:30 -0600 (MDT)

Final-Recipient: rfc822; harn@gov.ab.ca
Action: failed
Status: 5.0.0
Diagnostic-Code: X-BorderWare-Security-Platform; host
    142.229.229.10[142.229.229.10] said: 550 5.1.1 User unknown (in reply to
    RCPT TO command)
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