If I understand what you are asking, you (as the organizer) should open the
item on your own calendar. Add or remove the desired attendees and send an
update by using the Send Update option. Outlook prompts when you close the
meeting, if you forget. In most cases you have the option to only update the
folks that have changed.
I have try to drive in 3 cardinal rules for my users when teaching them to
schedule meetings... 1. Meetings ALWAYS have an organizer. (ownership) 2.
ALWAYS make a choice. (If someone sends you a meeting request, or
cancellation. You should always open the message and click Accept,
Tentative, or Decline.) 3. Meetings ALWAYS have a subject. (I hate it when
people schedule meetings without putting something in the subject line)