Service Pack 2 for Windows Vista extends the operating system's support for drivers that play nice with all Windows operating systems. Even as early as the first Beta of SP2 for Windows Vista and Windows Server 2008, the upgraded Windows Driver Model is permitting developers to get a taste of what the gold bits for the service pack will offer in terms of driver compatibility. According to Microsoft, the Registry Callback feature of WDM was kicked up a notch.

“Microsoft developers have upgraded and improved the Registry Callback feature of the Windows Driver Model (WDM). They have added 6 enumerations and 3 structures to the kernel architecture that will give you more flexibility in working with registry keys for filter drivers,” a member of the Windows Driver Kit team revealed.

At the start of December 2008 Microsoft made available for download the first Beta bits of Service Pack 2 for Windows Vista Service Pack 1 and Windows Server 2008 RTM/SP1. The Redmond company revealed that the 6 fresh enumerations added were: RegNtPreRestoreKey, RegNtPostRestoreKey, RegNtPreSaveKey, RegNtPostSaveKey, RegNtPreReplaceKey, and RegNtPostReplaceKey.

Three new structures are complementing the new enumerations: REG_RESTORE_KEY_INFORMATION, REG_SAVE_KEY_INFORMATION, and REG_REPLACE_KEY_INFORMATION.

With SP2 for Windows XP, Microsoft managed to come short of a new, standalone release of the Windows client. SP2 for Windows Vista is nowhere near a release of that scale, but simply a standard service pack comparable to SP1. Still, the tweaks, even if minor, are bound to deliver a positive impact on the user experience. The company introduced the Windows Driver Model in order to enable developers to built device driver source-code compatible with all Windows platforms.

“This new capability was added to Vista Service Pack 2 (SP2) at the last minute, and was not covered in the original doc release. Now we can tell you about it because the updated header has just been made available on Microsoft Connect. We wanted to publish this special announcement, so you can make use of this new technology right away,” the WDK team representative added.

Windows Vista Service Pack 2 (SP2) Beta is available for download here.