Changing recurring activities
To change a recurring activity
From the contact's Activities tab or one of the calendars, double-click the occurrence of the activity you want to change.
From the Schedule Activity dialog box, modify the field or fields you want to change, and then click OK. For field definitions, press F1. See Scheduling an activity for more information.
From the Edit Recurring Activity dialog box, select either Edit this occurrence or Edit all occurrences, as appropriate, and then click OK. For field definitions, press F1.