Windows Neptune build 5111

Neptune build 5.50.5111 is the only leaked build of Microsoft Neptune. It is also known as Microsoft Neptune Developer Release, even though in several places such as winver, it calls itself Windows 2000. It was compiled on December 10, 1999. It was sent to developers on the 27th. Other builds may have existed, most confirmations of other builds existing come from various files in Millennium builds holding a Neptune version number.