Add or remove attendees and resources
Open the meeting.
On the Actions menu, click Add or Remove Attendees.
To add an attendee or resource, click Add Others, click Add from Address
Book, enter the name you want to add in the Type name or select from list
box, and then click Required, Optional, or Resources.
To remove an attendee or resource, click the name you want to remove, and
then press DELETE on your keyboard.
Click OK, and then click Send Update
hope this helps
Cyndy