Windows Longhorn build 4067 (private/lddm dev tech(davidmo))

Windows Longhorn build 4067 (private/lddm_dev_tech(davidmo)) is a Milestone 7 build of Windows Longhorn. It was shown during WinHEC 2004 when Jim Allchin used it to demonstrate the then-new Longhorn Display Driver Model (later known as the "Windows Display Driver Model").

A presentation photograph featuring two screenshots of this build and a screenshot of build 4069 was first shared by Lucas Brooks (also known as ComputerHunter and mswin.bat) on 26 May 2021 — a high resolution version of the two screenshots were later leaked by ReflectiaX (aka BetaCollector) on the same day.