In one of the mail notification I have seen a message like "Please login with your AD credential". For a technical user we know what is AD and what is AD credential. But what about non-technical users. How should we convey the same meaning in different phrase.
The reason no one knows what an "AD credential" is (unlike, say, a Google account), is that AD is not anything in its own right (to end users). It's just an implementation of a log in that is used for something user facing.
You should tell the user to log in to whatever the user-facing thing is.
e.g. "Use your standard work log-in". Or whatever fits your case.
I think this is something that is mostly a question of internal procedures. At the university where I work they refer to it using terms like "central services username and password" but that is because we use the same login name and password for most centrally provided services. On a site where all the machines are "managed" and everyone uses their AD credentials to login to their computers, terms like "windows password" may be appropriate but on sites with lots of unmanaged machines where users commonly log in to their local machine with local credentials that could be more confusing than helpfull. Sites that have been running windows for a long time may use terms like "domain username and password".
The important thing is to find out what the existing procedures are at a site and stick to them. If you are writing software that is intended to be deployed in multiple locations then IMO you need to make such messages customisable so the local admins can set them up to reflect local conventions.