Horde Calendar application does not send alarm notifications for the planned events while event owner is offline. Calendar can send notifications on external email address while user, event creator, is logged in Horde Webmail. As soon as user leaves webmail interface, no notifications are being sent respectively.
This is program bug.
Horde alarm handler checks every minute if there is any events which must be warned about. But as it was said, handler works only with those who logged in.
Event owner's email address must be placed in file '
$conf['auth']['admins'] = array('email@example.com');
Multiple email addresses separated by commas can be added.
Copy the file '
/usr/share/psa-pear/pear/horde-alarms' to the directory '
Create cronjob task to execute '
/usr/share/psa-horde/admin/horde-alarms' with any interval you prefer, e.g.:
*/15 * * * * /usr/share/psa-horde/admin/horde-alarms
For Horde versions prior to 5.x (Plesk 9, 10, 11), please refer to this article.