• In Records, click Events.
     
    • Click Open an Event and search for and open the appropriate event.
     
    • On the Participants tab, select Guests in the right frame. In the left frame, double-click the guest to a registrant.
     
    • From the menu bar, select Participant, Convert to Registrant.
     
    • Save and Close the participant record.
     

    Alternative solution for prior versions: