title: Why is Referenced Component not be found in Visual Studio 2017 when it is found in Visual Studio 2015
body: <p>I have a solution with two projects - a primary project, and a unit test project.  When opening in Visual Studio 2015 all references are found and project builds successfully.  When opening in Visual Studio 2017 several but not all NuGet package references are not found and compile fails.  Some of the failed references are...</p>
  
  <ul>
  <li>System.Data.Common</li>
  <li>System.Net.Http</li>
  <li>System.Net.Http.WebRequest</li>
  <li>System.Security.Cryptography.Algorithms</li>
  <li>System.Security.Cryptography.Encoding</li>
  <li>System.Security.Cryptography.Primitives</li>
  <li>System.Security.Cryptography.X509Certificates</li>
  </ul>
  
  <p><a href="https://i.stack.imgur.com/OmdJl.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/OmdJl.png" alt="References"></a></p>
  
  <p>... but other NuGet references are found with no problem.  This solution was created with VS2015.  When viewing the .csproj file nothing out of the ordinary is jumping out.</p>
  
  <p>I am thinking of rebuilding it from scratch in VS2017 to try to identify the problem.</p>
  
  <p>Has anyone else experienced this problem, and/or has anyone any suggestions on why this is occurring and what should be done to facilitate a fix?</p>
  
  <p><strong>Update:</strong>
  I created a brand new VS2017 WebApi project referencing .NET 4.7.1, and compiled successfully.  I then added NuGet package System.Data.Common 4.3.0.  The NuGet install process appears to have completed with no errors, but still I am left with an invalid reference.  That was pretty easy to replicate.</p>