title: where is the "TargetFrameworkSDKToolsDirectory" was defined
body: <p>I was using msbuild build my sln and get error message "couldn't find 'AxImp.exe' which already exists under %Program files (x86)%\Microsoft sdks\windows\v8.1A. but seems it find sdk from v8.0A, output info point out the error was in Microsoft.Common.targets file(code see below). I didn't found where the "TargetFrameworkSDKToolsDirectory" was defined, anyone can help me?</p>
  
  <p>environment: winblue(4.5.1 sdk v8.1A) without visual studio.</p>
  
  <pre><code>    &lt;ResolveComReference
        TypeLibNames="@(COMReference)"
        TypeLibFiles="@(COMFileReference)"
        ResolvedAssemblyReferences="@(ReferencePath)"
        WrapperOutputDirectory="$(InteropOutputPath)"
        IncludeVersionInInteropName="$(IncludeVersionInInteropName)"
        KeyContainer="$(KeyContainerName)"
        KeyFile="$(KeyOriginatorFile)"
        DelaySign="$(DelaySign)"
        StateFile="@(_ResolveComReferenceCache)"
        TargetFrameworkVersion="$(TargetFrameworkVersion)"
        TargetProcessorArchitecture="$(ProcessorArchitecture)"
        NoClassMembers="$(ComReferenceNoClassMembers)"
        Silent="$(ResolveComReferenceSilent)"
        EnvironmentVariables="$(ResolveComReferenceEnvironment)"
        **SdkToolsPath="$(ResolveComReferenceToolPath)"**
        ExecuteAsTool="$(ComReferenceExecuteAsTool)"
        MSBuildArchitecture="$(ResolveComReferenceMSBuildArchitecture)"
        ContinueOnError="$(ContinueOnError)"&gt;
  
    &lt;**ResolveComReferenceToolPath** Condition="'$(ResolveComReferenceToolPath)' == ''"&gt;$(**TargetFrameworkSDKToolsDirectory**)&lt;/ResolveComReferenceToolPath&gt;
  </code></pre>