email code works in 2.7 but not in 3

[micksulley]

Running Python 3.8.10 and 2.7.18 under Mint 20.2
I am trying to generate an email on my IONOS 1 & 1 domain using this code

import smtplib
MAIL_2 = ['[email protected]']
FROM_ADDR = '[email protected]'
SUBJECT = 'Mail Subject via Ionos`'
BODY = 'Body of message'
PASSWORD = 'mypasswd'
SMTP_SERVER = "smtp.ionos.co.uk:587"
smtpserver = smtplib.SMTP(SMTP_SERVER)
smtpserver.ehlo()
smtpserver.starttls()
smtpserver.ehlo()
smtpserver.login(FROM_ADDR, PASSWORD)
header = 'To:' + ", " + MAIL_2[0] + '\n' + 'From: ' + FROM_ADDR + '\n' + 'Subject: ' + SUBJECT + '\n'
mmsg = header + '\n' + SUBJECT + '\n' + BODY + '\n\n'
smtpserver.sendmail(FROM_ADDR, MAIL_2,mmsg)
smtpserver.close()

If I run it in Python3 I get this error

Error:
Traceback (most recent call last):
  File "testmail-ionos01.py", line 14, in <module>
    smtpserver.starttls()
  File "/usr/lib/python3.8/smtplib.py", line 783, in starttls
    self.sock = context.wrap_socket(self.sock,
  File "/usr/lib/python3.8/ssl.py", line 500, in wrap_socket
    return self.sslsocket_class._create(
  File "/usr/lib/python3.8/ssl.py", line 1040, in _create
    self.do_handshake()
  File "/usr/lib/python3.8/ssl.py", line 1309, in do_handshake
    self._sslobj.do_handshake()
ssl.SSLError: [SSL: SSLV3_ALERT_ILLEGAL_PARAMETER] sslv3 alert illegal parameter (_ssl.c:1131)

If I run it in Python2.7 it works. I have looked with Wireshark and noticed that with 2.7 it uses TSLv1.3 but with 3.8 it uses TSLv1.2, I don't knw why or if this is relevant.
Also if I run similar code but using a gmail account it works in Python3.
Any idea how I can get this to work in Python3?
Thanks
Mick

[micksulley]

In case anyone has the same problem, this code works

import smtplib
MAIL_2 = ['[email protected]']
FROM_ADDR = '[email protected]'
SUBJECT = 'Mail Subject via Ionos`'
BODY = 'Body of message'
PASSWORD = 'mypasswd'
SMTP_SERVER = "smtp.ionos.co.uk:587"
smtpserver = smtplib.SMTP(SMTP_SERVER)
#smtpserver.ehlo()
#smtpserver.starttls()
smtpserver.ehlo()
smtpserver.login(FROM_ADDR, PASSWORD)
header = 'To:' + ", " + MAIL_2[0] + '\n' + 'From: ' + FROM_ADDR + '\n' + 'Subject: ' + SUBJECT + '\n'
mmsg = header + '\n' + SUBJECT + '\n' + BODY + '\n\n'
smtpserver.sendmail(FROM_ADDR, MAIL_2,mmsg)
smtpserver.close()

(Sorry but the insert code segment button does not seem to be working)
Note the two lines commented out. I don't know why this works but it does.

Larz60+ write Nov-04-2021, 05:14 PM:
Please post all code, output and errors (it it's entirety) between their respective tags. Refer to BBCode help topic on how to post. Use the "Preview Post" button to make sure the code is presented as you expect before hitting the "Post Reply/Thread" button.
Fixed, please don't forget

[Larz60+]

You should use f-string for lines 13 and 14

replace these two strings with:

mssg = f"TO:, {MAIL_2[0]}\nFromL {FROM_ADDR}\nSubject: {SUBJECT}\n" \
    f"\n{SUBJECT}\n{BODY}\n\n"

[micksulley]

Thanks I was not aware of f-string, just read up on it and it looks really good.