# Mail error 504 5.7.4 Unrecognized authentication type

**URL:** https://meta.discourse.org/t/mail-error-504-5-7-4-unrecognized-authentication-type/168921
**Category:** Self-hosting
**Created:** [November 1, 2020, 4:10pm UTC](https://meta.discourse.org/t/mail-error-504-5-7-4-unrecognized-authentication-type/168921 "2020-11-01T16:10:04Z")
**Posts on this page:** 1
**Showing post:** 6

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### Author: ![Wurzelseppi](https://avatars.discourse-cdn.com/v4/letter/w/eada6e/32.png) [@Wurzelseppi](https://meta.discourse.org/u/Wurzelseppi)
#### Post date: [November 9, 2020, 1:22pm UTC](https://meta.discourse.org/t/mail-error-504-5-7-4-unrecognized-authentication-type/168921/6 "2020-11-09T13:22:13Z")

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solved it now 🙂  
This one helped me with it:

> [@SMTP connection problem, docker installation](https://meta.discourse.org/t/smtp-connection-problem-docker-installation/41981/3):
>
> If you use [discourse\_docker](https://github.com/discourse/discourse_docker), try setting this in your app.yml: DISCOURSE\_SMTP\_AUTHENTICATION: login If you don’t use docker, try setting this in your discourse.conf: smtp\_authentication = login By default, Discourse uses plain authentication (which is not what MS Exchange expects):

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