With all Utility options, be sure to Choose Meeting first.
Use this utility to change an attendee's ID number to another ID number. You might use this when you add an attendee and then realize they are already in your individual table. This feature will change the ID# only. If you substitute one person for another and the new person is already in the individual table, you will need to change the name and email address to match what is in the INDV table.