Today, we released a new Windows 10 Preview Build of the SDK to be used in conjunction with Windows 10 Insider Preview (Build 18361 or greater). The Preview SDK Build 18361 contains bug fixes and under development changes to the API surface area.

The Preview SDK can be downloaded from developer section on Windows Insider.

For feedback and updates to the known issues, please see the developer forum. For new developer feature requests, head over to our Windows Platform UserVoice.

Things to note:

  • This build works in conjunction with previously released SDKs and Visual Studio 2017. You can install this SDK and still also continue to submit your apps that target Windows 10 build 1809 or earlier to the Microsoft Store.
  • The Windows SDK will now formally only be supported by Visual Studio 2017 and greater. You can download the Visual Studio 2017 here.
  • This build of the Windows SDK will install on Windows 10 Insider Preview builds and supported Windows operating systems.
  • In order to assist with script access to the SDK, the ISO will also be able to be accessed through the following URL: once the static URL is published.

Tools Updates

Message Compiler (mc.exe)

  • The “-mof” switch (to generate XP-compatible ETW helpers) is considered to be deprecated and will be removed in a future version of mc.exe. Removing this switch will cause the generated ETW helpers to expect Vista or later.
  • The “-A” switch (to generate .BIN files using ANSI encoding instead of Unicode) is considered to be deprecated and will be removed in a future version of mc.exe. Removing this switch will cause the generated .BIN files to use Unicode string encoding.
  • The behavior of the “-A” switch has changed. Prior to Windows 1607 Anniversary Update SDK, when using the -A switch, BIN files were encoded using the build system’s ANSI code page. In the Windows 1607 Anniversary Update SDK, mc.exe’s behavior was inadvertently changed to encode BIN files using the build system’s OEM code page. In the 19H1 SDK, mc.exe’s previous behavior has been restored and it now encodes BIN files using the build system’s ANSI code page. Note that the -A switch is deprecated, as ANSI-encoded BIN files do not provide a consistent user experience in multi-lingual systems.

Breaking Changes

IAppxPackageReader2 has been removed from appxpackaging.h

The interface IAppxPackageReader2 was removed from appxpackaging.h. Eliminate the use of use of IAppxPackageReader2 or use IAppxPackageReader instead.

Change to effect graph of the AcrylicBrush

In this Preview SDK, we’ll be adding a blend mode to the effect graph of the AcrylicBrush called Luminosity. This blend mode will ensure that shadows do not appear behind acrylic surfaces without a cutout. We will also be exposing a LuminosityBlendOpacity API available for tweaking that allows for more AcrylicBrush customization.

By default, for those that have not specified any LuminosityBlendOpacity on their AcrylicBrushes, we have implemented some logic to ensure that the Acrylic will look as similar as it can to current 1809 acrylics. Please note that we will be updating our default brushes to account for this recipe change.

TraceLoggingProvider.h / TraceLoggingWrite

Events generated by TraceLoggingProvider.h (e.g. via TraceLoggingWrite macros) will now always have Id and Version set to 0.

Previously, TraceLoggingProvider.h would assign IDs to events at link time. These IDs were unique within a DLL or EXE, but changed from build to build and from module to module.

API Updates, Additions and Removals


Read more: Windows 10 SDK Preview Build 18361 available now! - Windows Developer Blog

Download: Download Windows Insider Preview SDK