title: How to fix the error "Windows SDK version 8.1" was not found?
body: <p>I recently updated visual studio 2015 and now, when i try to build <em>any</em> project it always fails and i get the error</p>
  
  <blockquote>
    <p>Severity    Code    Description Project File    Line    Suppression State
        Error MSB8036 The Windows SDK version 8.1 was not found. Install the required version of Windows SDK or change the SDK version in the
    project property pages or by right-clicking the solution and selecting
    "Retarget solution".  Proj    D:\Program Files (x86)\visual studio
    2017\Common7\IDE\VC\VCTargets\Platforms\Win32\PlatformToolsets\v141\Toolset.targets   34</p>
  </blockquote>
  
  <p>I retargeted the solution as it said, and the problem persisted, even though the retargetting was completed.I decided to install visual studio 2017 because of this, and, lo and behold, it did the exact same thing.I'm also using windows 7.</p>
  
  <p>What is the problem and how can i fix it?</p>