This exception is raised when the server unexpectedly disconnects, or when an attempt is made to use the python mail SMTP instance before connecting it to a server. Clients sending outgoing mail should connect on port 587 and use starttls. To use port 465, you need to call smtplib.SMTP_SSL(). Currently, it calls smtplib.SMTP() .. so,change your PORT from 465 into 587 it. Also, you'll need to send the ehlo command before the starttls command, then again after the starttls command.   ... View more