I have an iPhone (iOS 7) that syncs reminders with an Exchange (2010) server. Everything works as expected except that when I mark an item as completed on the iPhone the synchronized task on the Exchange server is marked 100% complete, but the reminder is not dismissed. This causes any Outlook client using the same Exchange mailbox (2010 in this case) to pop up reminders for tasks that are already completed. I can clear the reminder in Outlook manually without any issues. Also, marking tasks as completed from Outlook dismisses the reminder as expected.
How can I get iOS or EAS to clear the reminder on the Exchange server when a task is marked as complete on the iPhone?
UPDATE: I have already tried multiple phones and multiple Exchange accounts on different servers so I don't think this is an isolated case.