Recently I have installed unity and wanted to try out building something for the HoloLens. But after days of trying out things I can't even build an empty unity project for the HoloLens. The steps I am taking are: New unity project. Build for UWP->Hololens. This works. Open resulting solution in visual studio and try to build there. Then the build breaks when issuing the command "SerializationWeaver." With the following traceback: Code (CSharp): Restoring NuGet packages... To prevent NuGet from restoring packages during build, open the Visual Studio Options dialog, click on the Package Manager node and uncheck 'Allow NuGet to download missing packages during build.' 1>------ Build started: Project: Assembly-CSharp-firstpass, Configuration: Debug ARM ------ 1> Running SerializationWeaver... 1> System.Collections.Generic.KeyNotFoundException: The given key was not present in the dictionary. 1> at System.ThrowHelper.ThrowKeyNotFoundException() 1> at System.Collections.Generic.Dictionary`2.get_Item(TKey key) 1> at UnityEditor.Scripting.Compilers.NuGetPackageResolver.Resolve() 1> at Unity.NuGetAssemblyResolver..ctor(String projectLockFile) 1> at usw.Weaver.ReaderParameters(String assemblyPath, ConversionOptions options) 1> at usw.Weaver.Weave() 1> at usw.Program.RunProgram(ConversionOptions options) 1> at usw.Program.Main(String args) 1>C:\b\GeneratedProjects\UWP\Assembly-CSharp-firstpass\Assembly-CSharp-firstpass.csproj(192,5): error MSB3073: The command ""C:\b\Unity\Tools\SerializationWeaver\SerializationWeaver.exe" "C:\b\GeneratedProjects\UWP\Assembly-CSharp-firstpass\bin\ARM\Debug\Unprocessed\Assembly-CSharp-firstpass.dll" "-pdb" "-verbose" "-unity-engine=C:\b\HoloLensTestProject\Unprocessed\UnityEngine.dll" "C:\b\GeneratedProjects\UWP\Assembly-CSharp-firstpass\obj\ARM\Debug\ARM\Debug" "-lock=C:\b\GeneratedProjects\UWP\Assembly-CSharp-firstpass\project.lock.json" "@C:\b\GeneratedProjects\UWP\Assembly-CSharp-firstpass\SerializationWeaverArgs.txt" "-additionalAssemblyPath=C:\b\HoloLensTestProject\Unprocessed" "-unity-networking=C:\b\HoloLensTestProject\Unprocessed\UnityEngine.Networking.dll"" exited with code 1. ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ========== I have tried the following running visual studio as administrator. Using a folder with no spaces as the build folder. Making the path as short as possible. I am at my wits end and I have no idea what the problem is... I am using unity 2017.1.0.f3 with visual studio community 2017. I have also I uninstalled unity 2017.1.0.f3 and installed the beta version unity 2017.2.0.b6 and I am having the exact same issue.