Office 365 - Connection refused

Note: I believe that Microsoft has turned off basic authentication as of January 2023:

https://techcommunity.microsoft.com/t5/exchange-team-blog/basic-authenti...

Hence, I'm going to close this issue as outdated for now, because we are now required to use OAuth or other authentication methods to connect to Office 365.

See ✨ Implement OAuth to support GMail/GSuite accounts Needs review for updates on this issue.