Outlook SMTP Server Issues (SMTPSyntaxError)

[supermathie (Michael Brown)]

I get the same result.

I don’t really have any suggestions other than this seems to be a problem with the mail server itself rather than Discourse.

I wouldn’t expect this server to be used for mail submission. Are you sure this is correct?

I see that other people have used a different submission server and gotten that working:

SMTP with office365?

Disabling security defaults may no longer be necessary with MFA enforcement. If you enable and then enforce MFA on a M365 account, you can go to the account’s MFA setup page and add an app password to use and bypass MFA. I got it working with a M365 Business Basic-licensed user with MFA enforcement, SMTP AUTH, and security defaults all enabled. I just had to turn up the SMTP open and read timeouts with two additional lines. 30 may be excessive, but 5 was too little. Working app.yml entry, as of…