Creating Appointments and Meeting Requests

Topic Last Modified: 2007-03-30

You can add an appointment to your calendar and request that others join you by sending them meeting requests. Microsoft Exchange Server 2007 provides Exchange Web Services, WebDAV, and CDOEX to implement this functionality.

CDOEX and ExOLEDB in Exchange Server 2003 Service Pack 2 (SP2) and Exchange 2007 create a new Entry ID value when an item is accepted, tentatively accepted, or declined. The new Entry ID value is assigned regardless of where the item is stored when the action is taken. This functionality differs from that of earlier versions of Microsoft Exchange. Because all the items keep the same Calendar ID property, other actions taken on the item are properly synchronized by the other clients. The original meeting request does not receive a new Entry ID value. A new Entry ID value is only applied when the action sets the acceptance status of the item. Updates to other parts of the item do not generate a new Entry ID. For example, updates that affect only the message body or meeting location, but not the acceptance status, do not affect the Entry ID.

If you cannot update legacy applications, you can update the following registry key to remove this behavior and process the calendar items based on Entry IDs:

HKEY_LOCAL_MACHINE\Software\Microsoft\EXCDO\Parameters

The DWORD value name is CDOCloneOnAccept. Set this value to zero (0) to disable this behavior.

You add an appointment by creating a Collaboration Data Objects (CDO) Appointment object, setting information about the appointment by using the object, and then saving the item to a folder. You create a meeting request from the Appointment object by using the CreateRequest method of the IAppointment interface. CDO creates a special message within a CalendarMessage object that you then send to attendees to invite them to the appointment.