As you are an expert, display all those hidden
menus and folders.
Go to the Active Directory Users and Computers,
Select View (Menu) then check: Advanced
Features. Now you should see the "LostAndFound"
folder and so be able to check for any orphaned users.
Select the DNS Icon, View (Menu),
Advanced. This brings the DNS "Cached Lookups"
folder into view.
Device Manager, Show Hidden Devices. This
useful for troubleshooting Non Plug and Play devices.