Mail delivery failed: returning message to sender

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Content-type: text/plain; charset=us-ascii

This message was created automatically by mail delivery software.

A message that you sent could not be delivered to one or more of its
recipients. This is a permanent error. The following address(es) failed:

  [email protected]
    (ultimately generated from [email protected])
    host gmail-smtp-in.l.google.com [74.125.142.27]
    SMTP error from remote mail server after end of data:
    550-5.7.26 Your email has been blocked because the sender is unauthenticated.
    550-5.7.26 Gmail requires all senders to authenticate with either SPF or DKIM.
    550-5.7.26
    550-5.7.26  Authentication results:
    550-5.7.26  DKIM = did not pass
    550-5.7.26  SPF [sourceware.org] with ip: [216.86.96.154] = did not pass
    550-5.7.26
    550-5.7.26  For instructions on setting up authentication, go to
    550 5.7.26  https://support.google.com/mail/answer/81126#authentication d2e1a72fcca58-82f8ec2af65si39708132b3a.189 - gsmtp

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Content-type: message/delivery-status

Reporting-MTA: dns; web02.zoozsolutions.ca

Action: failed
Final-Recipient: rfc822;[email protected]
Status: 5.0.0
Remote-MTA: dns; gmail-smtp-in.l.google.com
Diagnostic-Code: smtp; 550-5.7.26 Your email has been blocked because the sender is unauthenticated.
 550-5.7.26 Gmail requires all senders to authenticate with either SPF or DKIM.
 550-5.7.26
 550-5.7.26  Authentication results:
 550-5.7.26  DKIM = did not pass
 550-5.7.26  SPF [sourceware.org] with ip: [216.86.96.154] = did not pass
 550-5.7.26
 550-5.7.26  For instructions on setting up authentication, go to
 550 5.7.26  https://support.google.com/mail/answer/81126#authentication d2e1a72fcca58-82f8ec2af65si39708132b3a.189 - gsmtp

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