Good Morning, I've tried searching this and found some similarities, but not what I'm experiencing. I've been using an iPhone 4 with Microsoft Outlook 2010. Everything has been working fine until the other day it stopped syncing the calendar. While I still get the warnings if there is going to be a change to the computer from appointments I've set on the iPhone, it is not syncing to the computer. Also, appointments made on the computer are not going to the phone. Also, when plugging in the iPhone, iTunes thinks there is a calendar present that had been deleted sometime back. I've tried a reset on the phone, a restore from backup, and restore as new. I've reset the sync history and I've uninstalled and reinstalled iTunes and also uninstalled Microsoft Office Professional and reinstalled it too. It only happens for the calendar, the contacts are fine. All other syncing works too, including music, movies, apps and photos. Anyone have any suggestions? Thanks in advance.