SEATTLE – Microsoft executives are sharing publicly more details on the company's Windows Server roadmap, especially Windows Longhorn Server and follow-on releases.

Despite the fact that Microsoft has been pushing out regular test builds of Longhorn Server, "prior to the Beta 2 release, we hadn't really talked a lot about the functionality in Longhorn Server," acknowledged Jeff Price, a senior director on the Windows Server team, speaking at the company's annual Windows Hardware Engineering Conference (WinHEC) here on May 23.

Microsoft is releasing to testers Beta 2 builds of Longhorn Server, Windows Vista and Office 2007, starting this week. The Beta 2 build of Longhorn Server is build 5384, the same build number as Vista Beta 2.

Microsoft is planning to release a Beta 3 build of Longhorn Server in the first half of 2007, company officials told WinHEC attendees. The final Longhorn Server product will ship in the latter half of 2007, company officials added. Until recently, a number of company watchers were expecting Microsoft to release Longhorn Server in the first part of 2007.

Microsoft is planning to continue to roll out regular Community Technology Preview (CTP) test builds of Longhorn Server throughout its development life cycle. Some time this summer, the company is planning to allow customers to deploy Longhorn Server Beta 2, in combination with its IIS 7 Web server in production environments, Price said.

Beyond Longhorn Server, Microsoft is working on a number of other Windows Server releases in the next few years, said Bob Muglia, Senior Vice President of Microsoft's Server and Tools division. These include Windows Small Business Server R2, due out this summer, and Windows Server 2003 Compute Cluster Edition, due before the end of 2006.

In 2008, Microsoft is planning to release its mid-market Windows Server "Centro" product, aimed at customers with between 25 and 500 PCs connected to the Internet, Muglia told Microsoft Watch on Tuesday. Last fall, Microsoft officials said Microsoft was planning to release Centro in 2007. Centro still is not in beta and Muglia would not comment on when the product will go beta.

Microsoft is still expecting to release its next full-fledged version of Windows Server, currently known as Longhorn Server R2, in 2009, Muglia said, keeping to the team's schedule of releasing a new version of Longhorn Server every two years. While Longhorn Server R2's feature set is still in flux, Microsoft's Windows Server Virtualization hypervisor and Windows PowerShell ("Monad") technologies will be folded into Longhorn Server R2, Muglia confirmed.

Muglia hinted last summer that Microsoft also was planning to build a Longhorn Home Server product. Muglia declined to provide any additional timing or feature information on that product. All he would say is the idea of a Longhorn Home Server is "still an interesting concept."

Muglia said Microsoft has absolutely no plans to fold its WinFS file store back into Longhorn Server, even though WinFS is moving ahead at a steady clip. Microsoft is planning to release Beta 2 of WinFS in June at the TechEd conference.

"WinFS is like PowerShell," Muglia said. It needs a longer beta because it is a brand-new technology. "But we are looking at how we could incorporate some of that technology in the next version of SQL Server," code-named "Katmai," he said.

Katmai has yet to go to beta, and Muglia would not comment on when testers should expect to see the code. Microsoft watchers expect the company to release the final Katmai product in 2007 or 2008.

During a WinHEC session on the Longhorn Server roadmap, Price said that Microsoft is still considering whether to do a "focused (Windows Server) branch product" somewhere down the line.

Microsoft was dabbling a couple of years ago with the idea of doing a dedicated Windows Branch Server release, but decided that idea in the Windows Server 2003 R2 timeframe.