Calender Reminder does not work sinc update on version 8

since update on version 8 the calender reminder does not work.
I can make calendar entries but i don´t get any reminder.
Is there any solution for this problem?

OS Version?
email provider?
Any errors: menu/operations/errors or logs

Try: Right-click on offending calendar under email account and open “properties” - is default reminder set?
For all calendars right-click calendar icon (bottom), settings and set calendar reminder for all.

Try turning off the “Use system Notifications box”