Login credentials not working with Gmail SMTP

问题:

I am attempting to send an email in Python, through Gmail. Here is my code:

import smtplib


fromaddr = '......................'  
toaddrs  = '......................'  
msg = 'Spam email Test'  

username = '.......'  
password = '.......'

server = smtplib.SMTP('smtp.gmail.com', 587)  
server.ehlo()
server.starttls()
server.login(username, password)  
server.sendmail(fromaddr, toaddrs, msg)  
server.quit()

I get the error:

Traceback (most recent call last):
  File "email_send.py", line 18, in <module>
    server.login(username, password)
  File "C:\.....\Python\lib\smtplib.py", line 633
, in login
    raise SMTPAuthenticationError(code, resp)
smtplib.SMTPAuthenticationError: (535, b'5.7.8 Username and Password not accepte
d. Learn more at\n5.7.8 http://support.google.com/mail/bin/answer.py?answer=1425
7\n5.7.8 {BADCREDENTIALS} s10sm9426107qam.7 - gsmtp')

This seems to be a problem with the login. I am certain that my login details are correct, except for one thing. Should username be "[e-mail]", or simply "blah"? I tried both, same error.

Any idea whats wrong?

NOTE: all the periods are instead of password/email/file paths/etc.

回答1:

I ran into a similar problem and stumbled on this question. I got an SMTP Authentication Error but my user name / pass was correct. Here is what fixed it. I read this:

https://support.google.com/accounts/answer/6010255

In a nutshell, google is not allowing you to log in via smtplib because it has flagged this sort of login as "less secure", so what you have to do is go to this link while you're logged in to your google account, and allow the access:

https://www.google.com/settings/security/lesssecureapps

Once that is set (see my screenshot below), it should work.

Login now works:

smtpserver = smtplib.SMTP("smtp.gmail.com", 587)
smtpserver.ehlo()
smtpserver.starttls()
smtpserver.ehlo()
smtpserver.login('[e-mail]', 'me_pass')

Response after change:

(235, '2.7.0 Accepted')

Response prior:

smtplib.SMTPAuthenticationError: (535, '5.7.8 Username and Password not accepted. Learn more at\n5.7.8 http://support.google.com/mail/bin/answer.py?answer=14257 g66sm2224117qgf.37 - gsmtp')

Still not working? If you still get the SMTPAuthenticationError but now the code is 534, its because the location is unknown. Follow this link:

https://accounts.google.com/DisplayUnlockCaptcha

Click continue and this should give you 10 minutes for registering your new app. So proceed to doing another login attempt now and it should work.

This doesn't seem to work right away you may be stuck for a while getting this error in smptlib:

235 == 'Authentication successful'
503 == 'Error: already authenticated'

The message says to use the browser to sign in:

SMTPAuthenticationError: (534, '5.7.9 Please log in with your web browser and then try again. Learn more at\n5.7.9 https://support.google.com/mail/bin/answer.py?answer=78754 qo11sm4014232igb.17 - gsmtp')

After enabling 'lesssecureapps', go for a coffee, come back, and try the 'DisplayUnlockCaptcha' link again. From user experience, it may take up to an hour for the change to kick in. Then try the sign-in process again.

UPDATE:: See my answer here: How to send an email with Gmail as provider using Python?

回答2:

If you turn-on 2-Step Verification, you need generate a special app password instead of using your common password. https://myaccount.google.com/security#signin

回答3:

I had the same issue. The Authentication Error can be because of your security settings, the 2-step verification for instance. It wont allow third party apps to override the authentication.

Log in to your Google account, and use these links:

Step 1 [Link of Disabling 2-step verification]:

https://myaccount.google.com/security?utm_source=OGB&utm_medium=act#signin

Step 2: [Link for Allowing less secure apps]

https://myaccount.google.com/u/1/lesssecureapps?pli=1&pageId=none

It should be all good now.