Plesk needs an option to configure smtp as the sending option in horde. Right now you have to manually edit
/etc/psa-webmail/horde/horde/conf.php
change to smtp
/* $conf['mailer']['type'] = 'sendmail';*/
$conf['mailer']['type'] = 'smtp';
There is a if option that if safe mode is on then it will use smtp, but if not it uses sendmail
It should be able to be configured in the panel, not have it rely on safe mode or not.
/etc/psa-webmail/horde/horde/conf.php
change to smtp
/* $conf['mailer']['type'] = 'sendmail';*/
$conf['mailer']['type'] = 'smtp';
There is a if option that if safe mode is on then it will use smtp, but if not it uses sendmail
It should be able to be configured in the panel, not have it rely on safe mode or not.