TaskItem.ResponseState (Outlook)
Returns an OlTaskResponse constant indicating the overall status of the response to the specified task request. Possible return values are olTaskAccept - Task accepted, olTaskAssign - Task reassigned, olTaskDecline - Task declined, olTaskSimple - Task is a simple task and cannot be accepted, declined, or assigned. This constant is not a valid parameter to the TaskItem.Respond method.
Dim otrResponseState As OlTaskResponse
otrResponseState = Session.CreateSharingItem.Move.Items(1).ResponseState