To add or reactivate a completed a task: 

1.To create a new task, simply right-click on any area of the Task list section of the "Agenda" screen. On the context-menu, select the "Add task..." option. Note If a task is completed, the Task will be displayed as ticked and striped through.

2.To re-activate the task, you may simply deselect the "Complete" field. (untick the box).

To add or create a task: 

1.To create a new event, select the "Add task..." option. The "Untitled - Task" screen will be displayed.

2.Enter the subject (topic) of the task.

3.Select the Due date when the task should be completed.

4.Enter any additional information or notes for the task.

5.Click on the OK button to save the task.