I'm seeing problems related to Exchange calendar items at one of my clients.
The first issue is that some calendar items, created either in Outlook or on an iPhone, appear on the creator's own Outlook calendar, but not on another user's computer on which the creator's mailbox is configured as an additional mailbox in Outlook.
The second issue is that some calendar items that are created on an iPhone appear neither on the creator's Outlook calendar, nor on any other user's instance of the creator's calendar.
They are running Exchange 2003, and a mix of Outlook 2007 and 2010. The problem is independent of Outlook version.
I wonder if rights or flags are set differently on the iPhone-created events. I'm not sure how to check this on individual items, other than to view them in Outlook. Nothing stands out as being different when the items are viewed in Outlook, such as the private flag, which is not set.
There are no event log entries on the server that would indicate a problem, such as an ActiveSync error at the time when a calendar item is created on an iPhone.