Why can't I send emails to multiple recipients with this script?

Question

I get no errors nor bouncebacks, and the first recipient does receive the email. None of the others do.

The script:

#!/usr/bin/python
import smtplib

SMTP_SERVER = 'smtp.gmail.com'
SMTP_PORT = 587

recipient = 'email@domain.com; email2@domain.com;'
sender = 'me@gmail.com'
subject = 'the subject'
body = 'the body'
password = "password"
username = "me@gmail.com"

body = "" + body + ""

headers = ["From: " + sender,
           "Subject: " + subject,
           "To: " + recipient,
           "MIME-Version: 1.0",
           "Content-Type: text/html"]
headers = "\r\n".join(headers)

session = smtplib.SMTP(SMTP_SERVER, SMTP_PORT)

session.ehlo()
session.starttls()
session.ehlo
session.login(username, password)

session.sendmail(sender, recipient, headers + "\r\n\r\n" + body)
session.quit()

Kyle Jones · Accepted Answer · 2012-01-24T23:21:25.947

8

Semicolons are not the correct separator for addresses in recipient headers. You must use commas.

EDIT: I see now that you are using the library incorrectly. You're supplying a string which will always be interpreted as a single address. You must supply a list of addresses to send to multiple recipients.

edited Jan 24 '12 at 23:21

answered Jan 24 '12 at 22:55

Kyle Jones

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Using commas did not solve the problem. Do you have a URL for a specification on standard email header composition? – Trindaz Jan 24 '12 at 23:07
Thanks Kyle. I hadn't picked up on that because I assumed that because viewing the email 'details' in the GMail account of the first recipient showed the second recipient as having been CC'd that it was a problem at GMail's end. – Trindaz Jan 24 '12 at 23:33

score 2 · Answer 2 · answered Jan 24 '12 at 22:55

2

Recipients in the standard header must be separated by commas, not semicolons. I blame Microsoft Outlook for leading people to believe otherwise.

answered Jan 24 '12 at 22:55

Mark Ransom

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Using commas did not solve the problem. Do you have a URL for a specification on standard email header composition? – Trindaz Jan 24 '12 at 23:07
[RFC 2822](http://www.ietf.org/rfc/rfc2822.txt) section 3.6.3, which refers to an address-list, which is defined as `address-list = (address *("," address)) / obs-addr-list`. obs-addr-list uses commas, too. – Kyle Jones Jan 24 '12 at 23:12
@KyleJones, thanks for the link. Section 3.4 will be useful also since it defines `address-list`. – Mark Ransom Jan 24 '12 at 23:19
@Trindaz, please see the link added by Kyle Jones. – Mark Ransom Jan 24 '12 at 23:20

score 0 · Answer 3 · edited Jul 30 '13 at 23:43

0

Change this in your code:

recipient = ['email@domain.com','email2@domain.com']

headers = ",".join(headers)

session.sendmail(sender, recipient.split(","), headers + "\r\n\r\n" + body)

edited Jul 30 '13 at 23:43

Roman Luštrik

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answered Jul 30 '13 at 23:21

Amatus Saboor Husain

1

score 0 · Answer 4 · answered Jul 30 '13 at 23:52

0

Alternatively

recipient = ', '.join(recipient.split('; '))

if your recipients are a string of semicolon separated addresses.

answered Jul 30 '13 at 23:52

TheoretiCAL

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score 0 · Answer 5 · answered Jan 24 '12 at 22:57

You can, just put the emails in an array, and loop through the array for each email as in: (my python is rusty... so forgive my syntax)

foreach recipient in recipients
    headers = ["From: " + sender, "Subject: " + subject, "To: " + recipient, "MIME-Version: 1.0",  "Content-Type: text/html"]
    headers = "\r\n".join(headers)
    session.sendmail(sender, recipient, headers + "\r\n\r\n" + body)

Why can't I send emails to multiple recipients with this script?

5 Answers5

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