Change "Item.To" value in outlook when sending a message using VBA - vba

Question

I'm trying to change the email address in Send To field in Outlook when the user press send button. for example , if the current Item.To value = 'aaa#example.com' it becomes 'bbb#example.com'.
I can change the subject , but failed with Item.To ( is it security issue ? ) :
Private Sub Application_ItemSend(ByVal Item As Object, Cancel As Boolean)
If Item.Class <> olMail Then Exit Sub
Item.To = "bbb#example.com" ' Nope , It does not work
Item.Subject = "New Subject" ' It works
End Sub
Thanks

Answer 1

The MailItem.To property is used only for display names. You probably want to use the Recipients collection as in this slightly modified example from Outlook's Help on the MailItem.Recipients property:
Sub CreateStatusReportToBoss()
Dim myItem As Outlook.MailItem
Dim myRecipient As Outlook.Recipient
Set myItem = Application.CreateItem(olMailItem)
Set myRecipient = myItem.Recipients.Add("bbb#example.com")
myItem.Subject = "New Subject"
myItem.Display
End Sub

Answer 2

I'm the question owner. I chose #joeschwa answer but also I want to display my code that cancel the current message and create new one ( you can change the recipients , message contents and anything else ) :
Private Sub Application_ItemSend(ByVal Item As Object, Cancel As Boolean)
If Item.Class <> olMail Then Exit Sub
Dim newEm As String
Dim Rec As Recipient
Dim myItem As Outlook.MailItem
Dim myRecipient As Outlook.Recipient
Set myItem = Application.CreateItem(olMailItem)
myItem.Body = Item.Body
myItem.HTMLBody = Item.HTMLBody
myItem.Subject = Item.Subject & " RASEEL PLUGIN "
Cancel = True
For Each Rec In Item.Recipients
If InStr(1, Rec.AddressEntry, "#example.com", vbTextCompare) Then
newEm = "example#example.net"
Else
newEm = Rec.AddressEntry
End If
Set myRecipient = myItem.Recipients.Add(newEm)
myRecipient.Type = Rec.Type
Next
myItem.Send
End Sub

Answer 3

It works for me. However, when changing recipient, it is also necessary first to delete the previous recipient. For example,
x = .recipients.count
if x = 1 then .recipients(1).delete
.recipients.add "abc#dfg.com"