Или, если вам нужен весь скрипт:
Выполнить сценарий с параметром MailItem в качестве параметра.
Sub RewriteSubject(MyMail As MailItem)
Dim mailId As String
Dim outlookNS As Outlook.NameSpace
Dim myMailItem As Outlook.MailItem
mailId = MyMail.EntryID
Set outlookNS = Application.GetNamespace("MAPI")
Set myMailItem = outlookNS.GetItemFromID(mailId)
' Do any detection here
With myMailItem
.Subject = "Dept - " & mailItem.Subject
.Save
End With
Set myMailItem = Nothing
Set outlookNS = Nothing
End Sub