1. Log in to CaseFox.
2. In the navigation bar, click on the "Cases" tab.
3. Select the case in which you want to mark an event as completed.
4. Navigate to the "Calendar Event" tab.
5. Click on the tick mark icon labeled as "Mark as Completed," located to the right of the desired event.
6. Then, click on the "Update" button to mark the event as completed.