If you add the following code to the ThisOutlookSession module of the VBA editor, and either restart Outlook (saving the code) or run the macro Application_Startup from the editor, if you move a message to the Processed folder (a sub folder of Inbox) and the text 'Ticket No:' is missing from the subject the user should get a prompt warning that the ticket number is missing and the message is opened to enable it to be edited.
Option Explicit
Private WithEvents Items As Outlook.Items
Private Sub Application_Startup()
Dim olNS As NameSpace
Set olNS = GetNamespace("MAPI")
Set Items = olNS.GetDefaultFolder(olFolderInbox).folders("Processed").Items
lbl_Exit:
Exit Sub
End Sub
Private Sub Items_ItemAdd(ByVal item As Object)
Dim olFolder As Folder
On Error GoTo ErrorHandler
If InStr(1, item.Subject, "Ticket No:") = 0 Then
MsgBox "Add the ticket number to the subject, or move the message back where it came from!"
item.Display
End If
lbl_Exit:
Exit Sub
ErrorHandler:
MsgBox Err.Number & " - " & Err.Description
Err.Clear
GoTo lbl_Exit
End Sub