SMTP configuration error; no authenticators

Hi all

I’m trying to configure a nextcloud instance to send emails using our mailserver. I’ve entered in the details, and I’m confident that they are correct, but when I use the Test Email Settings button I get the following error:

A problem occurred while sending the email.
Please revise your settings.
(Error: Failed to authenticate on SMTP server with username 
"nextcloud@example.com.au" using 0 possible authenticators)

Zero authenticators sounds like something vital is missing on my installation.

Nextcloud is running on an Ubuntu 16.04 machine.

Thanks for the help

I am having the same issue! I am running the following:
Nextcloud 13.0.5 (on prem)
Apache 2.4.1.8
PHP version: 7.0.28-0
Ubuntu 16.04.1

I have an onsite Exchange server and admin access. I have tried a security account that I created for the nextcloud credentials as well as my own domain admin credentials.

The only configuration under Additional Settings - Email server that work are when I UNCHECK Authentication required BUT THIS WILL ONLY SEND EMAIL NOTIFICATIONS TO INTERNAL EMAIL ADDRESS. no outside email (e.g. @yahoo.com)

When I select:
Send Mode: SMTP
Encryption: none
Authentication method: Login
Authentication required: checked
Server address: (my smtp server) PORT 25 (also tried 565)
credentials: my domain admin account and also tried service account for nextcloud

I hit SEND MAIL and I get the following error:

“A problem occurred while sending the email. Please revise your settings. (Error: Failed to authenticate on SMTP server with username “nextcloudadmin” using 0 possible authenticators)”

I have to have this working for external email address’ to be able to send clients links to upload/download files with a password protected link.

Any update on this threat
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