Windows: Cannot build

I am trying to build x64 Debug ChakraCore from source, here's my setup:
- Windows 10.0.14393
- Visual Studio 2015 Pro 14.0.25431.01 Update 3
- Windows SDK 10.0.15063.468
- I've checkout the most recent source using git in the folder P:\dev\ChakraCore

(_Note that I have build ChakraCore on this machine successfully before, but that was just over a month ago. Because the build failed, and I was unable to fix it, I deleted all the files in ChakraCore source folder and downloaded them again using git. After it still failed, I try "repairing" my Visual Studio install and removed and reinstalled the Windows SDK. Despite all this, I am still unable to build._)

For brevity, I will only include the first error I see:
```
1>------ Build started: Project: Chakra.JITIDL, Configuration: Debug x64 ------
2>------ Build started: Project: CoreManifests, Configuration: Debug x64 ------
3>------ Build started: Project: wabt, Configuration: Debug x64 ------
4>------ Build started: Project: Chakra.Common.Codex, Configuration: Debug x64 ------
5>------ Build started: Project: Chakra.Common.Util, Configuration: Debug x64 ------
6>------ Build started: Project: Chakra.Common.Exceptions, Configuration: Debug x64 ------
7>------ Skipped Build: Project: pal, Configuration: Debug x64 ------
7>Project not selected to build for this solution configuration
8>------ Build started: Project: rl, Configuration: Debug x64 ------
1>Build started 04-07-2017 18:05:54.
1> 1>
1>InitializeBuildStatus:
1> Touching "P:\dev\ChakraCore\Build\VcBuild\obj\x64_debug\Chakra.JITIDL\Chakra.JITIDL.tlog\unsuccessfulbuild".
2>Build started 04-07-2017 18:05:55.
1> 1>
1>TRACKER : error TRK0005: Failed to locate: "midl.exe". The system cannot find the file specified.
```

It appears that midl.exe cannot be found. This is part of the Windows SDK and can be found on my computer in the following locations:
```
C:\Program Files (x86)\Windows Kits\10\bin\10.0.15063.0\arm64\midl.exe
C:\Program Files (x86)\Windows Kits\10\bin\10.0.15063.0\x64\midl.exe
C:\Program Files (x86)\Windows Kits\10\bin\10.0.15063.0\x86\midl.exe
```
I have no idea why it cannot find this file; can anybody explain why it would not be able to find it even though it is right there in the location where you would expect it to be?