Basic Administration > Supporting Collaboration > Calendar Administration
  
Calendar Administration
You can use the Calendar Management utility to view and change calendar schedules for all Windchill users. To view the system calendar, select Site > Utilities > Calendar Management. Click System Calendar.
Site administrators can set up the calendar environment for the system to include nonworking days such as company holidays, as well as allow users the ability to modify their own calendar schedules.
For more information, see Changing Calendar Schedules and Delegating Work.
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If you make changes to the Windchill system calendar that affect a project plan, you must manually refresh the plan to reflect these changes. Navigate to the plan information page and select Actions > Reschedule Plan.
Windchill system calendar changes are not reflected in newly created project plans until you restart the method server or perform the Reschedule Plan action at least once.