How to send an email with Gmail as provider using Python?

Asked 13/4, 2012 at 19:54 Answered 14/6, 2023 at 15:46

Solved python email smtp gmail smtp-auth

332

I am trying to send email (Gmail) using python, but I am getting following error.

Traceback (most recent call last):  
File "emailSend.py", line 14, in <module>  
server.login(username,password)  
File "/usr/lib/python2.5/smtplib.py", line 554, in login  
raise SMTPException("SMTP AUTH extension not supported by server.")  
smtplib.SMTPException: SMTP AUTH extension not supported by server.

The Python script is the following.

import smtplib

fromaddr = '[email protected]'
toaddrs  = '[email protected]'
msg = 'Why,Oh why!'
username = '[email protected]'
password = 'pwd'
server = smtplib.SMTP('smtp.gmail.com:587')
server.starttls()
server.login(username,password)
server.sendmail(fromaddr, toaddrs, msg)
server.quit()

Merle answered 13/4, 2012 at 19:54 Comment(1)

Also, for VPN users, if the issue still persists, turn your VPN off. That worked for me. – Kimberleykimberli 8/12, 2019 at 18:38

230

You need to say EHLO before just running straight into STARTTLS:

server = smtplib.SMTP('smtp.gmail.com:587')
server.ehlo()
server.starttls()

Also you should really create From:, To: and Subject: message headers, separated from the message body by a blank line and use CRLF as EOL markers.

E.g.

msg = "\r\n".join([
  "From: [email protected]",
  "To: [email protected]",
  "Subject: Just a message",
  "",
  "Why, oh why"
  ])

Note:

In order for this to work you need to enable "Allow less secure apps" option in your gmail account configuration. Otherwise you will get a "critical security alert" when gmail detects that a non-Google apps is trying to login your account.

Tactical answered 13/4, 2012 at 19:57 Comment(19)

invoking server.sendmail(fromaddr, toaddrs, msg) the second parameter, toaddrs must be a list, toaddrs = ['[email protected]'] – Champaign 20/8, 2013 at 6:59

As of August 2014 this now raises smtplib.SMTPAuthenticationError: (534, '5.7.9 Application-specific password required. – Bissonnette 27/8, 2014 at 18:6

For me though, I had to enable an 'app' password to log in using an @google account to send emails via python: support.google.com/accounts/answer/… – Bissonnette 27/8, 2014 at 18:13

Finally, what's the best way to use this syntax to send to multiple addresses at once? – Bissonnette 27/8, 2014 at 18:15

Here's a link on how to mail multiple people: #8856617 – Bissonnette 27/8, 2014 at 18:43

Why \r\n? Why not just \n? – Altigraph 29/3, 2016 at 14:15

SMTP specifies CRLF as line ending – Tactical 29/3, 2016 at 14:22

how would one specify adding an attachment in this case? – Ineradicable 11/5, 2016 at 12:12

Note: When sending to Gmail, I had to use both \r\n but when I sent to Hotmail or a custom host, I didn't have to, I just used a multiline string. With a multiline string, Gmail put it all on one line and didn't read anything after the first header definition. – Dahlgren 19/5, 2016 at 6:56

SMTPException: STARTTLS extension not supported by server. – Guarantor 19/10, 2016 at 9:54

@De̲̳̳ath-Stalke̲̳̳r: Just checked the documentation and tried the code, it's functioning as expected. Perhaps you hit a temporary error or your connection to gmail is being interfered with. – Tactical 19/10, 2016 at 9:59

The problem is that almost EVERYTHING says to use HELO and doesn't mention EHLO. I wonder what the difference is... – Gardia 27/10, 2016 at 5:11

@FoxDonut I started fiddling with SMTP 20 years ago and back then nothing much did 'HELO'. 'EHLO' is an extended helo and is asked by clients wanting an extended response containing server capabilities. – Tactical 28/10, 2016 at 22:25

I once logged in to an SMTP server by telnet and sent EHLO by typo. After I tried HELO many times but the response was different. It took hours to figure out that EHLO is actually a command that SMTP understand and I did the typo. – Barrett 26/1, 2017 at 11:3

Why does this work? I found docs explaining that EHLO is an extended hello, but I do not understand how that results in fixing this bug. – Month 13/11, 2019 at 15:21

@P.V. This answer was for a problem that was posted 7 years ago. It was right at the time. SMTP protocol requires the first action of an SMTP connection to be an HELO or a EHLO from the client. The smtplib library is/was a low level library which required you to know how to use the protocol. The only bug was in the OP's code for not starting the connection with an EHLO. – Tactical 13/11, 2019 at 15:34

smtplib is not fully thread-safe, so it will have issues sending concurrent messages. If that's your requirement, use Gmail REST API – Ghibelline 18/3, 2020 at 10:7

less secure apps is no longer an option, we must use the google api instead – Arcane 1/3, 2021 at 13:6

Link to Gmail Developers API: developers.google.com/gmail/api – Oden 2/7, 2022 at 17:13

325

def send_email(user, pwd, recipient, subject, body):
    import smtplib

    FROM = user
    TO = recipient if isinstance(recipient, list) else [recipient]
    SUBJECT = subject
    TEXT = body

    # Prepare actual message
    message = """From: %s\nTo: %s\nSubject: %s\n\n%s
    """ % (FROM, ", ".join(TO), SUBJECT, TEXT)
    try:
        server = smtplib.SMTP("smtp.gmail.com", 587)
        server.ehlo()
        server.starttls()
        server.login(user, pwd)
        server.sendmail(FROM, TO, message)
        server.close()
        print 'successfully sent the mail'
    except:
        print "failed to send mail"

if you want to use Port 465 you have to create an SMTP_SSL object:

# SMTP_SSL Example
server_ssl = smtplib.SMTP_SSL("smtp.gmail.com", 465)
server_ssl.ehlo() # optional, called by login()
server_ssl.login(gmail_user, gmail_pwd)  
# ssl server doesn't support or need tls, so don't call server_ssl.starttls() 
server_ssl.sendmail(FROM, TO, message)
#server_ssl.quit()
server_ssl.close()
print 'successfully sent the mail'

Belief answered 14/9, 2012 at 12:19 Comment(14)

Very nice sample thanks. One think I noticed is if I want to use an SSL connection I had to remove server.starttls() – Phonetist 14/4, 2014 at 20:13

Probably something obvious, but why do I need to pass TO and FROM to the sendmail function if we already have them in the message? Thank you! – Divide 8/11, 2014 at 16:4

Doesn't work anymore unfortunately: smtplib.SMTPAuthenticationError: (534, '5.7.14 <accounts.google.com/… ... Please log in via your web browser and\n5.7.14 then try again.\n5.7.14 Learn more at\n5.7.14 support.google.com/mail/bin/answer.py?answer=78754 ... Then i got a mail from google, that there has been a suspicious connection attempt. – Dextrin 13/2, 2015 at 17:0

@Dextrin - all you need to do is create an app password and use it in lieu of your account password. Create an app password here: security.google.com/settings/security/apppasswords – Uchida 15/4, 2015 at 1:14

@Dextrin : I just got a fix for the issue you where facing. Google has a setting to allow access for less secure apps you just have to turn it 'On'. you can get there from : Google-->my account -->Sign-in & security--> Connected apps & sites--> scroll down and you will find 'Allow less secure apps ' – Lettering 7/8, 2015 at 21:16

Thanks, although hiding exceptions with a print statement is terrible practice. Let them propagate or rethrow appropriately. – Walliw 25/3, 2016 at 17:2

The port 465/ssl example is the only python./gmail example that works for me. Amazing! – Firebox 26/4, 2016 at 9:45

Thank you. For port 465 i failed to called ehlo(). Now its working. – Beethoven 8/6, 2016 at 5:7

If your gmail is secured by Two-Factor Authentication, you must first generate an application specific password --> then use that app-password for in the above example code (this is very important because then you aren't writing your password down anywhere in cleartext AND you can revoke the app-password at any time). – Teresetereshkova 12/11, 2016 at 16:46

Is it possible there's an extra \n in here? From: %s\nTo: %s\nSubject: %s\n\n%s? Deleting the last \n made attachments work for me. – Tunnage 26/5, 2017 at 6:45

interestingly, if you take out the comma join for recipients and only pass a single email address, the email still sends! even though the string is something like 'j,o,h,n,d,o,e,...'. I only discovered this after looking in my sent folder – Gaucho 8/2, 2018 at 16:54

I don't like any of the options available: I have to enable 2-step authentication (which I feel is overkill) in order for google to allow me to create an app password, otherwise it says "The setting you are looking for is not available for your account", but I'm wary of changing the account setting that allows less secure applications. Is there another option? – Hairdo 30/8, 2018 at 22:6

2021-12-09: this answer works fine using google app password feature on a 2-factor-authenication account (both SMPT on port 587 and SMPT_SSL on port 465) – Hymeneal 11/12, 2021 at 18:34

Warning: mind your quotes! I use an .ini file to store my email address as user_name="{my_user_id}@gmail.com" and this solution did not work until I removed double quotes in the ini file. That was the quick fix - still deciding how to handle this fun fact. – Hymeneal 11/12, 2021 at 18:38

230

You need to say EHLO before just running straight into STARTTLS:

server = smtplib.SMTP('smtp.gmail.com:587')
server.ehlo()
server.starttls()

Also you should really create From:, To: and Subject: message headers, separated from the message body by a blank line and use CRLF as EOL markers.

E.g.

msg = "\r\n".join([
  "From: [email protected]",
  "To: [email protected]",
  "Subject: Just a message",
  "",
  "Why, oh why"
  ])