Freescout Connection to Mailcow SMTP fails with Error 535

[PadawanDeluxe]

PHP version: 8.2
FreeScout version: 1.8.152
Database: MySQL
Are you using CloudFlare: No
Are you using non-official modules: No

Hey folks,
I am trying to setup Freescout with an Mailcow server to send out my emails. We spin up the Freescout instance using a webspace package and have configured mail access. All in all recieving works fine, but sending causes issues. What I can see from the Freescout site is:

`<< 535 Incorrect authentication data

!! Expected response code 235 but got code "535", with message "535 Incorrect authentication data
" (code: 535)
!! Expected response code 235 but got code "535", with message "535 Incorrect authentication data
"
Log data:
++ Starting Swift_SmtpTransport
<< 220-webspaces.server.net ESMTP Exim 4.97.1 #2 Sun, 15 Sep 2024 14:06:40 +0200
220-We do not authorize the use of this system to transport unsolicited,
220 and/or bulk e-mail.`

What I have done on the mailcow site is veryfing the access to the mailbox as well as checking SSL/TLS settings on the server. I am able to access the mailbox either via SSL or TLS. This means that the auth coming from freescout is not clear to me and I am rising up this issue here. I am looking for help to tweak the authentication using the SMTP section. Following along the Q&A as well as the Docs didnt help me out on this one.

thanks in advance for all of your help and patience!

regards
Carsten

[KlausdB]

Hi Carsten
I use Mailcow server with Freescout and have no issues.
My SMTP settings are: Port 465 with SSL Encryption

The only other thing that I can think that may interfere is the "Allow to send as" setting in the server / mailbox settings. You can set disable sender check to test if that may be the cause.

Klaus

[freescout-help]

You'll need to figure it out by yourself diagnosing it on your server.