Do one of the following:
Propose a new time for a meeting
Whenever you make a counter proposal, it is sent with a default message saying that you want to propose a new time, but that you have tentatively accepted the meeting. You can change this default message to say that you want to propose a new time, and that you are declining the meeting by doing the following:
Note You can also change this setting for individual meetings. In the open meeting request, on the Action menu, click either Decline and Propose a New Time or Tentative and Propose a New Time.
Accept a new meeting time