Microsoft today pushed out another new Windows 10 SDK preview for developers to check out. Coming in at build 18334, the latest release brings the SDK preview in line with the most recent Windows 10 Fast ring build, and there are some new tools and changes to take note of.

Here’s a look at what’s available with Windows 10 SDK Preview Build 18334:

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

In addition to the above, there are a number of API updates, additions, and removals to be aware of. For the full list, you can check out Microsoft’s complete release notes.

As with previous SDK releases, build 18334 can be installed with Visual Studio 2017 alongside prior SDKs. If you’re a developer, you can download Windows 10 SDK Preview Build 18334 from the Insider downloads page now.