Discourse - SMTP from OVH

Did anyone succeed with OVH Email-Pro and Discourse?
I tried these:

DISCOURSE_SMTP_ADDRESS: pro2.mail.ovh.net
DISCOURSE_SMTP_PORT: 587
DISCOURSE_SMTP_USER_NAME: admin@mydomain.com
DISCOURSE_SMTP_PASSWORD: mypassword
DISCOURSE_SMTP_ENABLE_START_TLS: true           # (optional, default true)
DISCOURSE_SMTP_AUTHENTICATION: login  # (you need to add this line)

But I’m getting:
504 5.7.4 Unrecognized authentication type

when testing with ./discourse-doctor.

I’m using paid OVH Email-Pro account.

I’m losing faith that I’ll ever have a working Discourse install. I’ve tried numerous free email accounts and Discourse was never able to send emails with them. I even tried my own postfix, but no luck.
Does this work only with Mailgun? :frowning: