Several users asked me how to add secure to the message subject before sending the message.

I need a way to change the subject of an email after I hit send. Specific example: If I have a subject that says "meeting", after I hit send I would like the subject to be automatically changed to "meeting {Secure Message}"

You can either use an ItemSend macro to add Secure automatically, or use macro to selectively add Secure to the message.

ItemSend

Private Sub Application_ItemSend(ByVal Item As Object, Cancel As Boolean)

Dim strSecure As String
 
strSecure = "Secure " & Item.Subject
Item.Subject = strSecure
     
End Sub

To use ItemSend and add Secure to the subject of some, but not all, messages, you need to use an If statement. If the message meets the condition, Secure is added to the subject.

In this example, we're testing for domains in the address. If a match is found, the subject is edited and sent. To send to all EXCEPT some domains, use
If InStr(LCase(strRecip), arrDomain(n)) = 0 Then.

Private Sub Application_ItemSend(ByVal Item As Object, Cancel As Boolean)
Dim Recipients As Outlook.Recipients
Dim recip, strRecip As String
Dim i, n
Dim arrDomain As Variant
Dim strSecure As String

Set Recipients = Item.Recipients
  For i = Recipients.Count To 1 Step -1
    Set recip = Recipients.Item(i)
      strRecip = recip.Address & " " & strRecip
  Next i

' Set up the array
arrDomain = Array("domain1.com", "domain2.com")
 
' Go through the array and look for a match, then do something
For n = LBound(arrDomain) To UBound(arrDomain)
    If InStr(LCase(strRecip), arrDomain(n)) > 0 Then
        strSecure = "Secure " & Item.Subject
        Item.Subject = strSecure
        Exit Sub
  End If
Next n

End Sub

Macro Button on Ribbon

To use this macro, customize the message ribbon by adding a new button near the existing Send button.

Sub AddSecure()
Dim Item As MailItem
Set Item = Application.ActiveInspector.CurrentItem()
  
Dim strSecure As String
 
strSecure = "Secure " & Item.Subject
Item.Subject = strSecure
Item.Send
 
End Sub

Add Secure to Reply

Like the previous macro, you'll create a button on the ribbon for this macro. Click the button instead of Reply.

Public Sub SecureReply()
 Dim objApp As Outlook.Application
 Dim objItem As MailItem
 Dim strSecure As String

 Set objApp = Application
 Set objItem = objApp.ActiveExplorer.Selection.Item(1)
 Set Item = objItem.Reply
 
strSecure = "Secure " & Item.Subject
Item.Subject = strSecure
Item.Display
End Sub

How to use Macros

First: You will need macro security set to low during testing.

To check your macro security in Outlook 2010 or 2013, go to File, Options, Trust Center and open Trust Center Settings, and change the Macro Settings. In Outlook 2007 and older, it’s at Tools, Macro Security.

After you test the macro and see that it works, you can either leave macro security set to low or sign the macro.

Open the VBA Editor by pressing Alt+F11 on your keyboard.

To use the macro code in ThisOutlookSession:

1. Expand Project1 and double click on ThisOutlookSession.
2. Copy then paste the macro into ThisOutlookSession. (Click within the code, Select All using Ctrl+A, Ctrl+C to copy, Ctrl+V to paste.)

More information as well as screenshots are at How to use the VBA Editor