Can't export Window Store solution and open on Visual Studio

Please bear with me, I am a beginner in both Unity and Visual Studio.

I am trying to follow the first Hololens tutorial, so I created a simple project and I am trying to export it as a Visual Studio Solution. However, although I set all the build settings as instructed by Microsoft, when I open the .sln file I get an empty Visual Studio with a Solution for my app that says '0 projects' and nothing in it.

Anything that I might be missing?

UPDATE:

I hadn't noticed, but Unity gives me this error:
DirectoryNotFoundException: Could not find a part of the path "C:\Program Files (x86)\Windows Kits\10\Platforms\UAP\10.0.10240.0\Platform.xml".
System.IO.FileStream..ctor (System.String path, FileMode mode, FileAccess access, FileShare share, Int32 bufferSize, Boolean anonymous, FileOptions options) (at /Users/builduser/buildslave/mono/build/mcs/class/corlib/System.IO/FileStream.cs:292)
System.IO.FileStream..ctor (System.String path, FileMode mode, FileAccess access, FileShare share)
(wrapper remoting-invoke-with-check) System.IO.FileStream:.ctor (string,System.IO.FileMode,System.IO.FileAccess,System.IO.FileShare)
System.Xml.XmlUrlResolver.GetEntity (System.Uri absoluteUri, System.String role, System.Type ofObjectToReturn)
Mono.Xml2.XmlTextReader.GetStreamFromUrl (System.String url, System.String& absoluteUriString)
Mono.Xml2.XmlTextReader..ctor (Boolean dummy, System.Xml.XmlResolver resolver, System.String url, XmlNodeType fragType, System.Xml.XmlParserContext context)
System.Xml.XmlTextReader..ctor (Boolean dummy, System.Xml.XmlResolver resolver, System.String url, XmlNodeType fragType, System.Xml.XmlParserContext context)
System.Xml.XmlReader.Create (System.String url, System.Xml.XmlReaderSettings settings, System.Xml.XmlParserContext context)
System.Xml.XmlReader.Create (System.String url, System.Xml.XmlReaderSettings settings)
System.Xml.Linq.XDocument.Load (System.String uri, LoadOptions options)
System.Xml.Linq.XDocument.Load (System.String uri)
UnityEditor.Scripting.Compilers.UWPReferences.GetPlatform (System.String folder, System.String version) (at C:/buildslave/unity/build/Editor/Mono/Scripting/Compilers/UWPReferences.cs:111)
UnityEditor.Scripting.Compilers.UWPReferences.GetReferences () (at C:/buildslave/unity/build/Editor/Mono/Scripting/Compilers/UWPReferences.cs:64)
PostProcessUAP.get_UWPReferences () (at C:/buildslave/unity/build/PlatformDependent/MetroPlayer/Extensions/Managed/PostProcessUAP.cs:21)
PostProcessUAP.GetAdditionalReferenceAssembliesDirectories () (at C:/buildslave/unity/build/PlatformDependent/MetroPlayer/Extensions/Managed/PostProcessUAP.cs:47)
PostProcessWinRT.RunSerializationWeaver () (at C:/buildslave/unity/build/PlatformDependent/WinRT/SharedSources/CSharp/PostProcessWinRT.cs:400)
PostProcessWinRT.Process () (at C:/buildslave/unity/build/PlatformDependent/WinRT/SharedSources/CSharp/PostProcessWinRT.cs:124)
UnityEditor.WSA.BuildPostprocessor.PostProcess (BuildPostProcessArgs args) (at C:/buildslave/unity/build/PlatformDependent/MetroPlayer/Extensions/Managed/ExtensionModule.cs:155)
UnityEditor.PostprocessBuildPlayer.Postprocess (BuildTarget target, System.String installPath, System.String companyName, System.String productName, Int32 width, Int32 height, System.String downloadWebplayerUrl, System.String manualDownloadWebplayerUrl, BuildOptions options, UnityEditor.RuntimeClassRegistry usedClassRegistry, UnityEditor.BuildReporting.BuildReport report) (at C:/buildslave/unity/build/Editor/Mono/BuildPipeline/PostprocessBuildPlayer.cs:186)
UnityEditor.HostView:OnGUI()