Symptoms
Is there a way to send escalation notifications only to the people which have incomplete tasks. Currently, the escalation is sent to all users who are assigned the task, even if they have completed the task.
Diagnoses
This can be done, but it must be done on the Event Escalation level, and not the Activity Escalation level.
Resolution
_1: When specifying which user will get the escalation email, select Specify instead of Destination User.
_2: When specifying who the email will be sent to (To:), use the context browser to navigate to the Workflow Context browser. Expand the Activity Destination Instance node and then expand the User node. Drag the Email node over to the To: box. This will only send emails to the users who have not actioned the task.