Have an existing app that uses smtp to a gmail server to send emails, client is changing the email system and I need to switch to using smtp.office365.com as the server however it isn’t working. I am using the same parameters as I use in a different program written in another language (Java) which is working successfully. Talking to the person who administers the email server he says that it requires TLS 1.2 and wont work with anything lower. Is there a way to force the smtp mail client to use tls 1.2 when you specify TLS is required?