EWS Managed API
Topic Last Modified: 2006-12-06
To register to receive notification of specific events
If the event sink is a Component Object Model (COM) class (not a script), you must register it in the Microsoft® Windows® operating system.
Create a store item with a content class of urn:content-class:storeeventreg. The item is now an event registration item.
Set properties on the item.
Save the item to the store location where you want to keep the event notifications. The registration is now complete.