I keep getting the error message "apple outlook DAV has stopped working"

My phone and I pad all of the sudden just stopped syncing with my desktop. I have had my phone for over a year when 4s first came out and everything was syncing fine. Then all the sudden it stopped. I keep getting the error message "apple outlook DAV has stopped working". I have rebooted, checked for duplicates, signed in and out of the cloud and still nothing. Has anyone had this problem and know of a good way to handle it. Also, now my phone and Ipad don't sync with the cloud either. Please help.