The Interested Parties section under a Product entry lets users subscribe to get emails for certain events related to that product. Simply add an entry under the list, selecting the user and checking off the different types of events that interest them.
Once added, any activity in the system relating to that product and that event will result in an email being sent to that user informing them of what happened. For example if a task is added to the product and the user subscribed to that event, they will receive an email when a new task is added or its status is updated.
In addition to this section there is also a global Interested Parties list under the List tab where users can subscribe to events related to any product.
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