Windows Server 2004 was first developed in 1997 as Windows Codename Jaguar.
1996-1997: Early development[]
On August 10, 1996 FICROSOFT CORPATION just started the development but the development were not released until June 10, 1997. Here are the early beta and builds: Build 1: The first ever Windows Jaguar. But it was known as Windows Sydney until August 1, 1997.
Build 2182: Released on August 1, 1997.
Build 2188: Released on September 27, 1997.