You may can create a new calendar from scratch or you can copy one of existing calendars.
The "Work Days Calendar (create)" form
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Then, you can manually specify the holidays which fall on work days by double-clicking the appropriate days. Similarly, redefine the days off that will be work days.
The toolbar buttons
Click Reset If you want to mark days off on the calendar according to one of the available templates: Sun-Thu, Mon-Fri, or Sat-Thu.
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Click the Save button to save the new calendar or the Save and close button to save the calendar and close the form. For description of other buttons, refer to List toolbar.