Microsoft Friday announced a significant change in plans for the next major release of Windows, code-named Longhorn.

The new Windows storage subsystem code-named WinFS will not be part of the Longhorn operating system, as had been previously planned.

Microsoft said WinFS will be delivered after the Longhorn release. Greg Sullivan, a lead product manager at Microsoft, said WinFS will follow the Longhorn "client" operating system release but Microsoft doesn't know when it will be complete.

The company said only that WinFS, which provides advanced data organization and management capabilities, will be in beta testing when the Longhorn client is released.

The target date for broad availability of the Longhorn client operating systems is 2006, according to Microsoft. The company said the expected release date for the Longhorn server operating system continues to be 2007, but it provided no information on whether the WinFS storage subsystem will be ready by that time.

"We've heard loud and clear from customers that they want improved productivity, easier deployment, increased reliability and enhanced security, as well as the many innovations we've been working on. We've had to make some trade-offs to deliver the features corporate customers, consumers and OEMs are asking for in a reasonable time frame," said Jim Allchin, group vice president of Microsoft's platforms group, via a prepared statement. "Our long-term vision for the Windows platform remains the same."

Microsoft had laid out key details of its Longhorn vision during its Professional Developers Conference last October in Los Angeles. WinFS was one of three critical elements that company officials said would be part of the Longhorn release. The other two were the graphics subsystem, code-named Avalon, and communication technologies for building advanced Web services, code-named Indigo.

Microsoft said it announced during a meeting today with hundreds of its developer evangelists that the Avalon and Indigo subsystems will be made available for Windows XP and Windows Server in 2006. Avalon and Indigo are part of the new WinFX developer technologies due with Longhorn.

At its Los Angeles conference in October, Microsoft had said that a beta version of Longhorn would be available in the second half of 2004. The beta release was subsequently pushed to the first half of 2005. Sullivan said the beta remains on target for the first half of next year.

Sullivan said WinFS is being developed independently of the client and server operating systems. "We'll deliver it independently so it will then be available to users of Longhorn client and server. Exactly when that happens, we don't know," he said. WinFS could be applied and installed on one of the existing operating systems, he said.

From Computer World