A grade scale must be assigned to the CRN before proceeding. The Grade Scale field will be blank. You can enter a grade scale directly, or you can select a valid value for the CRN. The Schedule Table (SSBSECT) is updated with this value when you save the changes.
If students are registered for the CRN, and no grades have been rolled to academic history (the Grades Rolled check box is clear), you can select another grade scale from the lookup button.