If the state of application compatibility for Windows XP clients is in its infancy, app compatibility for the various Whistler server betas is embryonic. That fact, more than almost anything else, is a guarantee that Microsoft won't ship the 32-bit or 64-bit version of Windows 2002 until 2002, according to testers working with the beta builds of the product.

Microsoft announced officially earlier this week that it is christening the various Whistler server builds as "Windows 2002." The company has been saying since earlier this year that its Whistler server products would follow its Windows XP client products to the market by several months.

While various Microsoft partners and industry watchers have speculated that the company is running late on its Windows XP clients, citing schedule alleged to have leaked to the Web from within Microsoft as proof. Microsoft itself is still targeting this summer as the date it plans to release its Windows XP Home and Professional clients for manufacture.

According to Microsoft's most current internal release schedule, a copy of which was viewed by Ziff Davis, Microsoft is planning to release its Windows XP clients to manufacturing on July 25th.

At the same time, according to the internal schedule, Microsoft is targeting July 2nd as a tentative date to release a third beta of its 32-bit and 64-bit Windows 2002 server products. The latest RTM (release to manufacturing) date for those operating system is now January 23, 2002, the schedule reads.

What's not working

Why is Windows 2002 lagging Windows XP by six months at the moment? Testers working with Beta 2 releases of the Windows 2002 server iterations (Server, Advanced Server and Datacenter Server) note that--just as in the case of the client--application compatibility is a problem.

According to a copy of the Whistler server Beta 2 release notes viewed by Ziff Davis, quite a few of Microsoft's own .Net server applications aren't working at all at this point.

These include Microsoft's core applications, such as Exchange 2000, Application Center 2000, BizTalk Server 2000, Systems Management Server 2.0 and Internet Security and Acceleration Server 2000. According to the release notes, Microsoft is telling testers that these products will work with a future beta release.

At the same time, Microsoft admitted that it has no intentions of providing compatibility between Windows 2002 and older versions of some of its enterprise applications products, such as Exchange 5.5, SNA Server 4.0, Proxy Server 2.0 and SiteServer 3.0.

"The .Net Enterprise Server applications will support Whistler server compatibility in an upcoming beta," said Michael Stephenson, lead product manager with Microsoft's Windows.Net Servers group. "Microsoft's goal is to have all the applications that run on Windows 2000 Servers today also run on Whistler server."

While Windows 2002 servers will include a number of new features, especially those aimed at making Active Directory deployment easier, the next-generation servers are considered by Microsoft an "evolutionary," rather than a "revolutionary," upgrade.

Testers said it is unclear which new features are causing the compatibility issues between Microsoft's .Net applications and Whistler Beta 2. And Microsoft officials did not offer any further explanation.

The new, new Whistler schedule

Windows XP clients Beta 1 10/31/00 Beta 2 3/23/01 RTM 7/25/01 Windows 2002 servers Beta 1 10/31/00 Beta 2 3/23/01 Beta 3 7/2/01 RTM 1/23/02 Source: Alleged Microsoft Internal schedule, updated 4/30/01

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