Can I grab the userID from the Login Page using Active Directory credentials?

On our utility server, we have users accessing via the web. They are prompted for their user ID and password which is their network/windows (or active directory).

We are using @Name([CN]; @Username) to get their user name, but when we do a lookup on this name in active directory, we have duplicates.

So, we are wondering if we can grab their login ID from the login page or if there is another field we can get after they’ve logged in with their network/windows credentials.

I’ve done searches to find documentation on the login page but have yet to find the correct search criteria combination to get any results.

Thanks in advance for any help.

anne