Microsoft last week released second beta versions of Windows Vista, Office 2007 and Longhorn Server. Though the firm said it is on track to deliver Vista to enterprise customers in November, it gave itself a get-out clause, adding that the release date depends on Beta 2 feedback.

The new betas were unveiled at the Windows Hardware Engineering Conference in Seattle. Microsoft chairman Bill Gates said the previews are a major step in delivering new platforms for the next decade of computing. Office 2007 is due this autumn along with Vista, while Longhorn Server is now due in the second half of 2007.

Microsoft said a broad Windows Vista preview programme will start within weeks. Currently, Vista Beta 2 and Longhorn Server Beta 2 are only available through MSDN or TechNet subscriptions. The Office Beta 2 is available for download from Microsoft’s web site. An Application Compatibility Toolkit has also been released to test software running under Windows 2000 or XP for Vista compliance.

“We got feedback that last time we didn’t get this out fast enough with XP SP2,” said Will Poole, senior vice-president of Microsoft’s Market Expansion Group. “For the first time, we have this out early, and we’re enabling you to test products without even running Vista.”

Microsoft also made available a unified licence for all components of WinFX, the new programming model for developing Vista applications.

However, doubts have again been raised about the Vista shipping date. Poole said it should be available to firms in November, but this depends on customer reactions to Beta 2. Analyst Gartner stood by its prediction that broad availability of Vista would follow nine to 12 months after Beta 2, which would put it in early 2007.

Michael Silver of Gartner also warned that Windows 2000 users must move quickly to test and deploy Vista. “Although Microsoft will support Windows 2000 until mid-2010, we’ve already heard that new versions of some of Microsoft’s apps do not support Windows 2000,” he added.