Checking the invitation status for an activity
When you schedule an activity with other users, you can check the invitation status. The invitation status lets you see whether the users accepted, tentatively accepted, or declined the invitation.
To check the invitation status for an activity
Locate the activity, and then double-click it.
Click the Availability tab.
Click the Show Invitation Status button.
The Invitation Status dialog box appears. The users and their status are listed in the User and Status columns.