Use of the the built in php mailer is no longer supported

after upgrading from NC 13.0.6 to NC14.0.1 the installation comes back with all sorts of unexpected issues.

One of these issues is:
Use of the the built in php mailer is no longer supported. [Please update your email server settings :arrow_upper_right:]

on one hand this is annoying since php mailer was working in all versions before and there might be good reasons to use it instead of a SMTP server.

on the other hand… the updater is checking all kinds of stuff before upgrade (or pretends to do so) but there isn’t even a warning that a core feature will be disabled by upgrading.

Further: the manual clearly states (https://docs.nextcloud.com/server/14/admin_manual/configuration_server/email_configuration.html):
Supported methods are php, smtp, sendmail

Nextcloud version (eg, 12.0.2): 14.0.1
Operating system and version (eg, Ubuntu 17.04): 18.04
Apache or nginx version (eg, Apache 2.4.25): Nginx 1.14.0
PHP version (eg, 7.1): 7.2

The issue you are facing:
Use of the the built in php mailer is no longer supported

Is this the first time you’ve seen this error? (Y/N): y

Steps to replicate it:

  1. run Nextcloud 13
  2. upgrade to NC14.0.1 using updater app
  3. face issue

Did you try to select one of them? Before this was done by php mailer, so perhaps you only need to verify the settings or re-enter a password. I don’t know exactly, but it should still work without setting up your own smtp server.

smtp is the only choice available in the mail server srttings dialogue

Then open an issue on github.com/nextcloud/documentation/issues and ask for clarification.

done.

Someone on the forum mentioned setting up postfix mail server on the host running NC, and use those details in the SMTP config in order to keep sending mail.

locally (same host running NC) installed sendmail/postfix was always supported.
This option is still available.
Use of any other smtp server is still an option, too.

The question was not, how to find another way of sending emails.
The question was, why php mailer is not an option anymore, even it is an officially documented feature and there is not mention anywhere that upgrading from NC13 to NC14 would disable this feature.