As far as I know, since Windows Vista Microsoft has replaced the message with a generic one (see https://social.technet.microsoft.com/Forums/windows/en-US/1440ff2b-e9b5-47b2-ab8b-2e4cb845c9b2/changemodifyedit-the-failed-password-complexity-dialog?forum=itprovistasecurity).
I know, it's not the best option but there is the possibility to show a message on every logon via GPO (Computer Configuration -> Policies -> Windows Settings -> Security Settings -> Local Policies -> Security Options -> "Interactive logon: Message text for users attempting to log on", maybe this can help you.