ERROR – 535 auth failure

installation
1

Basically, I am facing the same issue as described here: Job exception: 535 Authentication failed

For some reason our E-Mail outbound does not work anymore and I get now an error 535. I rechecked the E-Mail account. I can login there and use it from Apple Mail. SMTP Mail sending I also tested with Apple Mail. But discourse gives me this error message “ERROR – 535 auth failure”. I am not sure, how to proceed here. Is SMTP still supported?

My tests until now:

  1. I tried different Mail Accounts
  2. I tested the Mail Accounts with another Mail Software
  3. I updated to the latest discourse version. (3.2.0.beta1-dev)

Any help would be appreciated.

2

maybe have a look here?

1 Like
4

Yes, I did. But the error preserves.

Is there anything else, we could try? Any help would be appreciated.

6

Do you have a copy of the error with more detail in?

From a search, you could try checking and re-entering your credentials in your app.yml.

7

Unfortunately, I don’t know how to retrieve more detail here. Is there any option to enable more debug information in that case? On the command line there is no context. The error appears in the UI.

8

Isn’t there something like verbose debugging output?

10

What other information would help? The remote server is telling you authentication failed. There’s not a lot more we can say.

Do you have 2FA or MFA turned on for this mail account? This might prevent SMTP AUTH from working.

If not, can you try SMTP by hand to see if the authentication works?

You need to first construct the authentication string (a base64-encoded string of username␀username␀password)

I suggest using python:

○ → ipython3

In [1]: import base64

In [2]: import getpass

In [3]: u, p = 'michael', getpass.getpass()
Password: (paste or type password here)

In [4]: base64.b64encode(f'{u}\x00{u}\x00{p}'.encode()).decode()
Out[4]: 'bWlxxxxxxxxxxxxxxxxxxxxxxxxxxx'

(please change michael to your actual SMTP username if you do this)

:rotating_light: DO NOT SHARE THIS STRING IT IS YOUR PLAINTEXT PASSWORD

and then doing SMTP by hand, e.g.:

○ → openssl s_client -starttls smtp -connect mail.my.domain:587
CONNECTED(00000003)
…
---
250 SMTPUTF8
AUTH PLAIN bWljaGFlbABtaWNoYWVsAHBhc3N3b3Jk ← the password "password"
535 5.7.8 Error: authentication failed: authentication failure
AUTH PLAIN bWlxxxxxxxxxxxxxxxxxxxxxxxxxxx ← the real password
235 2.7.0 Authentication successful
RSET
250 2.0.0 Ok
QUIT
221 2.0.0 Bye
closed

If that doesn’t work, the credentials probably really are bad. If it does work… we’ll look further.

1 Like