Topic: Postfix not processing CC field when mail sent from Python smtplib

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When i try to send an email using my python code that's using smtplib, email was sent successfully but CC header is ignored by postfix for some reason.
When i receive an email, i see the recipient in CC field and i can use "Reply All". But CC recipient hasn't received that email and Postfix logs do not show that email was sent to CC. If i use "Reply All", CC will then receive my reply.

This is the header that is being formed by Python.

Content-Type: multipart/mixed; boundary="===============0783044642835671299=="
MIME-Version: 1.0
From: admin@example.com
To: someemail@other.com
Cc: cc-someemail@other.com
Subject: Bill

Content-Type: text/plain; charset="us-ascii"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit

Auto generated. Bill is: 1234
Content-Type: application/octet-stream
MIME-Version: 1.0
Content-Transfer-Encoding: base64
Content-Disposition: attachment; filename= Racun.pdf


Any ideas why would this be ignored? Much appreciated!


Re: Postfix not processing CC field when mail sent from Python smtplib

Specify Cc addresses in your Python code (e.g. the "sendmail()" function).
The From/To/Cc/Bcc headers in submitted message are not read by Postfix, only the "MAIL FROM:", "RCPT TO:" smtp directives are used by Postfix to pick up sender/recipients.


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Re: Postfix not processing CC field when mail sent from Python smtplib

But sendmail() from smtplib doesn't support CC.
If i add a "list" of recipients like ["name@email.com", "surename@email.com"] it will all add them to "To" field.

Ahhhhhhhh, i get it now!!
If i form the headers like i did in first email, but pass a list of recipients to sendmail() it will actually work!
Thanks Zhang!!