Labels in Formulas That Are Not Defined Names
Extreme speed supports defined names and their use in formulas, but not the Microsoft Excel Accept labels in formulas option which allows cell labels to be used in formulas without defining them as names:
Example message: "Unable to interpret formula at cell location [Book1.xls]Sheet1!A1. (Code #5514 - Undefined identifier)"
Workaround: For best results, use defined names instead of cell labels in formulas.