How to fix ssl.SSLError: [SSL: WRONG_VERSION_NUMBER] wrong version number (_ssl.c:1056)?

Question

I am trying to send an email with python, but it keeps saying ssl.SSLError: [SSL: WRONG_VERSION_NUMBER] wrong version number (_ssl.c:1056) . Here is my code:

server = smtplib.SMTP_SSL('smtp.mail.com', 587)
server.login("something0@mail.com", "password")
server.sendmail(
"something0@mail.com", 
"something@mail.com", 
"email text")
server.quit()

Do you know what is wrong?

Answer 1

The port for SSL is 465 and not 587, however when I used SSL the mail arrived to the junk mail.

For me the thing that worked was to use TLS over regular SMTP instead of SMTP_SSL .

Note that this is a secure method as TLS is also a cryptographic protocol (not unlike SSL).

import smtplib, ssl

port = 587  # For starttls
smtp_server = "smtp.gmail.com"
sender_email = "my@gmail.com"
receiver_email = "your@gmail.com"
password = input("Type your password and press enter:")
message = """\
Subject: Hi there

This message is sent from Python."""

context = ssl.create_default_context()
with smtplib.SMTP(smtp_server, port) as server:
    server.ehlo()  # Can be omitted
    server.starttls(context=context)
    server.ehlo()  # Can be omitted
    server.login(sender_email, password)
    server.sendmail(sender_email, receiver_email, message)

provided thanks to the real python tutorial

Answer 2

Code to send email via python:

import smtplib , ssl
import getpass
server = smtplib.SMTP_SSL("smtp.gmail.com",465)
server.ehlo()
server.starttls
password = getpass.getpass()   # to hide your password while typing (feels cool)
server.login("example@gmail.com", password)
server.sendmail("example@gmail.com" , "sender-example@gmail.com" , "I am trying out python email through coding")
server.quit()

#turn off LESS SECURE APPS to make this work on your gmail

Answer 3

That usually happens when the client doesn't understand the ServerHello message that is supposed to come from the server. Typical usecases:

1. Server responds using a protocol version that's not understood by client (either too new or too old)
2. Server responds with complete garbage data (that's a sign that it's not using encryption)

I played a bit with openssl 's arguments (I didn't paste all my attempts in the snippet below), and got various errors. Apparently, it's #2. : smtp.mail.com doesn't use enctyption .

 [cfati@cfati-ubtu16x64-0:~]> ~/sopr.sh *** Set shorter prompt to better fit when pasted in StackOverflow (or other) pages *** [064bit-prompt]> python3 -c "import ssl, smtplib;print(ssl.OPENSSL_VERSION);smtplib.SMTP_SSL(\\"smtp.mail.com\\", 587)" 2>&1 | grep rror ssl.SSLError: [SSL: UNKNOWN_PROTOCOL] unknown protocol (_ssl.c:645) [064bit-prompt]> [064bit-prompt]> openssl s_client -connect smtp.mail.com:587 CONNECTED(00000003) 140043409938072:error:140770FC:SSL routines:SSL23_GET_SERVER_HELLO:unknown protocol:s23_clnt.c:794: --- no peer certificate available --- No client certificate CA names sent --- SSL handshake has read 7 bytes and written 305 bytes --- New, (NONE), Cipher is (NONE) Secure Renegotiation IS NOT supported Compression: NONE Expansion: NONE No ALPN negotiated SSL-Session: Protocol : TLSv1.2 Cipher : 0000 Session-ID: Session-ID-ctx: Master-Key: Key-Arg : None PSK identity: None PSK identity hint: None SRP username: None Start Time: 1567195256 Timeout : 300 (sec) Verify return code: 0 (ok) --- [064bit-prompt]> [064bit-prompt]> python3 -c "import smtplib;smtplib.SMTP(\\"smtp.mail.com\\", 587);print(\\"Done.\\")" Done. 

Ways to get rid of the error:

• Move away from this server to (a decent) one that does use encryption (I'm not an expert in this area, so I can't provide one)
• Connect to the server without SSL , using [Python 3.Docs]: class smtplib. SMTP ( host='', port=0, local_hostname=None, [timeout, ]source_address=None) . But, beware of all the security risks! (data (including passwords) sent in clear text (as @tedvm noticed)). There are lots of URL s (eg [Norton.US]: What is encryption and how does it protect your data? ) explaining why you shouldn't do this