Sets or returns an OlShowItemCount constant that indicates whether to display the number of unread messages in the folder or the total number of items in the folder in the Navigation Pane. Read/write.
expression.ShowItemCount
expression Required. An expression that returns one of the objects in the Applies To list.
The ShowItemCount property does not work with public folders.
This Microsoft Visual Basic for Applications (VBA) example displays the unread count for the Inbox in the Navigation Pane.
Sub ShowTotalItemCount()
Dim olApp As New Outlook.Application
Dim nmsName As Outlook.NameSpace
Dim fldFolder As Outlook.MAPIFolder
Set nmsName = olApp.GetNamespace("MAPI")
Set fldFolder = nmsName.GetDefaultFolder(olFolderInbox)
fldFolder.ShowItemCount = olShowUnreadItemCount
End Sub