When Microsoft released its first Windows Vista Community Technology Preview (CTP) build this fall, company officials said they did so in the name of transparency.

But testers say Microsoft is being anything but transparent about the November CTP build of the next version of Windows, which some company watchers are speculating will go to a wider pool of testers on Tuesday.

However, one tester, who requested anonymity, said he believed there would be no November CTP, and possibly no additional CTPs at all.

"Microsoft has unofficially cancelled the November CTP for Windows Vista to Technical beta testers," the tester said. In fact the future of the Vista CTP program itself was unclear, he said.

"Microsoft has yet to say anything about this though, as usual," the tester said.

CTPs, pioneered by Microsoft's developer division with Visual Studio, are interim pre-release versions of a product that are not beta quality. They represent a snapshot of a product under development at a given time, and are meant for developers and testers who aren't afraid to be on the bleeding edge.

At the Microsoft Professional Developers Conference in mid-September, company officials said they were hoping to release monthly CTPs of Vista. So far, Microsoft has released both September and October Vista CTPs.

Microsoft told some partners that it also planned a November CTP. Just before Thanksgiving, Microsoft made available to its pool of elite Technology Adoption Program (TAP) partners Build 5259 of Vista, which a number of testers and others in the Microsoft blogging community considered to be the November CTP.

Microsoft officials declined to comment on Build 5259 or to discuss features or functionality changes planned for the November CTP.

However, Microsoft is planning to hold on Tuesday "the first in a series of conference calls hosted by members of the Windows Vista team," according to a company statement. "Each call will focus on the status of the Windows Vista development process and the actions recommended for Microsoft's partners and customers around our CTPs and other milestones."

Screen shots of Vista Build 5259 showed a number of user-interface tweaks — including the first appearance of an "orb-shaped" Start button. Windows Antispyware (now known as Windows Defender) seemed to be integrated into the product, as expected. Windows Media Player 11, or at least a placeholder for it, seemed to be part of the build, and Instant Off seems to be working, testers said.

But a few days after releasing 5259, Microsoft made available a developer kit for a different and slightly later Vista build, 5262, leading to speculation that 5259 was not the November CTP, after all.

"I have tried 5259 as well for the past couple of days and I can say that it is completely unstable and totally buggy. As you know, 5259 was a possible November CTP candidate and I think this would have been a disaster for Microsoft," said Sandro Villinger, a Microsoft Most Valuable Professional (MVP) and Webmaster of the Windows Tweaks Web site. " I also hear that 5262 will be the Nov. CTP, but I haven't gotten a confirmation from Microsoft on that one."

As of Tuesday morning, Microsoft had not committed to releasing a December CTP of Vista. Up until a month or so ago, the Vista team was hoping to release Beta 2 —
which Microsoft has said will be feature-complete — some time in December, company officials had told partners privately. Now, Beta 2 is expected in January, according to testers, who requested anonymity.

Villinger said he recently was able to look at Build 5270, which he believes could become the December CTP.

Build 5270 "shows some major improvements in terms of functionality (e.g. a completely new defrag module, "Windows Defender" is finally integrated, a functional Parental Controls filter) and it ran pretty fast on a mediocre test machine. However, the UI (user interface) does look like the one in previous Vista Builds except that the Display properties have been replaced by some sort of activity center called 'Personalize Windows' (also seen in Build 5259)."

Microsoft is still holding to its mid-2006 release-to-manufacturing (RTM) date for Vista. If it makes that date, PC makers should be able to preload Vista on PCs by fall 2006, well in time for the holiday 2006 sale season.