My calendar is not syncing since I upgraded from 4s to 5s.

Hello, I just upgraded to the 5s. Everything seems to be syncing just fine, my work calendar which is on outlook and all the speciality calendars such as FB, holidays, birthdays, events via other sites. The only one I can't get to sync is my personal calendar which runs out of MSN. The dates were entered via my 4S and saved but for some reason my mail and contacts synced but not my appointments. I've checked the msn account and all boxes are checked. So what else do I need to do? Thank you in advance.