Microsoft has started preparing preparing its partners for the eventual arrival of Windows Vista SP1 (Service Pack 1).

Microsoft officials have not yet released the schedule and details for a service pack update for Microsoft's Windows Vista operating system. But Microsoft has now started openly referencing the upcoming Vista SP1 release in documentation on its website.

Industry experts have long predicted the arrival of a Windows Vista SP1 release. Some observers have been looking for Service Pack 1 even since before the launch of the OS in late 2006. But Microsoft remains steadfastedly tight-lipped on what its plans for the SP1 update might be.

Windows Vista - the definitive review

On 7 June, Microsoft posted documentation for a Windows Automated Installation Kit on its Download Center portal that applies to a product dubbed Windows Vista SP1 Beta 3.

The Windows AIK (Windows Automated Installation Kit) is designed to help OEMs (original equipment manufacturers), system builders and corporate IT departments deploy the OS on to new hardware, Microsoft said.

As part of the announcement, Microsoft posted a document which indicates that Windows Vista SP1 has been under development since at least February 2007, the date amended to the file which provides an informational overview of the download.

Some German researchers were also recently able to sneak a screenshot that references Vista SP1 from a presentation at the WinHEC (Windows Hardware Engineering Conference) in Los Angeles in mid-May.

Microsoft officials didn't immediately respond to calls seeking comment on the details of Vista SP1.

When SP2 for Microsoft Windows XP first arrived in August 2004 it set off a wave of discontent as many businesses had problems installing the update.

However, it is widely perceived that the release significantly benefited Windows users once it could be swallowed, particularly in the area of improving security.

Some Microsoft partners have also alluded to the update publicly.

On 19 April, Intel CEO Paul Otellini was asked how Vista sales would impact his company's 2007 sales projections on a conference call, and he replied that "[Vista] deployment [in enterprises] will actually happen when the Service Pack gets released in the fourth quarter time frame, probably the October-November time frame."

In early April, a software patch blog posted over 100 fixes it said are expected to be included in Windows Vista SP1.

Sources close to Microsoft have confirmed that the company is currently testing SP1.

The blog poster, former Microsoft employee Ethan Allen, owner of the The Hotfix blog and Web site is predicting that SP1 will include device driver and software compatibility technology that many users had hoped would be available in the OS from the start.

Among them could be support for third-party USB and Firewire devices such as digital cameras, in particular products from Sony Corp. that have been having compatibility problems with Vista, Allen said.

There also will be patches to improve the TV playback and other Media Center capabilities in Vista, as well as to repair inconsistencies with the power management functions such as sleep and hibernation modes, he said.

Allen claims that Vista SP1 will not include a heavy dose of security updates.

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