Windows XP build 3599

Windows XP Professional x64 Edition build 3599 is the earliest known build of Windows XP Professional x64 Edition. The registry hives for this build are present in the Windows Server 2003 source code.

This build is a private compile, as evidenced by the username in the build tag. It was built by Dave Cutler, a primary architect of Windows NT, who was leading development of Windows on AMD64 at the time of this build's compilation.