Windows 7 build 6429

Windows 7 build 6429 is the earliest known build of Windows 7. This build was shown by Microsoft in a remote desktop from Windows XP from the DTM-AudioFidelityTestingLocal_Training (dead link) and DTM-AudioFidelityLogs_Training videos.

Due to its earliness, it still identifies itself as Windows Vista and the kernel version is still 6.0. It also has Service Pack 1 branding.