title: The type 'HttpRequestMessage' is defined in an assembly that is not referenced
body: <p>When i build locally it works, but my VSTS hosted 2017 instance build fails with the following message:</p>
  
  <pre><code>[error]apps\Ascend.Identity\AccountController.cs(126,17): Error CS0012: The type 'HttpRequestMessage' is defined in an assembly that is not referenced. You must add a reference to assembly 'System.Net.Http, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'.
  </code></pre>
  
  <p>Locally, there is also a yellow triangle in the reference list.
  <a href="https://i.stack.imgur.com/jYSsF.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/jYSsF.png" alt="enter image description here"></a></p>
  
  <p>but it still builds</p>
  
  <p>and the reference is there in csproj</p>
  
  <p><a href="https://i.stack.imgur.com/yH7C3.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/yH7C3.png" alt="enter image description here"></a></p>
  
  <p>and the package is restored from nuget (packages.config) </p>
  
  <pre><code> &lt;package id="System.Net.Http" version="4.3.3" targetFramework="net472" /&gt;
  </code></pre>