Advanced Redmine Notifications
E-mail notification of issues due date you are involved in (Assignee, Author, Watcher, Custom field)
Follow the plugin installation procedure at http://www.redmine.org/wiki/redmine/Plugins.
The plugin runs as a rake task so you have to set it up in cron or task sheduler
1 0 * * * root cd /opt/redmine && rake redmine:send_reminders_all RAILS_ENV=production
You can setup options in administration menu.