Zimbra Desktop Calendar won't sync

I initially was using iCal for my calendaring but I wanted to switch to Zimbra Desktop. When I was using iCal I was using Zimbra sync and it worked great. For some reason the Zimbra Desktop won't sync with my online calendar. I might be doing something wrong but after reading several other posts it seems that there are some issues. I also tried to sync my Google Calendar without success. :confused:

I upgraded to Zimbra Desktop 7 from Zimbra Desktop 2 and now my calendar no longer has any of my Zimbra online calendars. Desktop 7 only has the local folders with Calendar and trash...