Obrigado pelo seu comentário rápido CharlieRB. Esse é o meu código:
Sub ClearPrivateFlag()
Dim ol As New Outlook.Application
Dim ns As Outlook.NameSpace
Dim fdMail As Outlook.MAPIFolder
Dim objItem As Object
Dim objAppt As MailItem
Dim i, nCount As Integer
Set ns = ol.GetNamespace("MAPI")
'Reference the default Mail folder
Set fdMail = ns.GetDefaultFolder(olFolderInbox)
i = 1
nCount = fdMail.Items.Count
Do While i < nCount
Set objItem = fdMail.Items(i)
If objItem.Class = olMailItem Then
Set objAppt = objItem
If (objAppt.Sensitivity = olPrivate) Then
objAppt.Sensitivity = olNormal
MsgBox objAppt
End If
End If
i = i + 1
Set objItem = Nothing
Set objAppt = Nothing
Loop
Set fdCalendar = Nothing
Set ns = Nothing
Set ol = Nothing
End Sub