title: Installing Win10 SDK (any version) hangs every time
body: <p>I'm trying to install the Win10 SDK (any version - logs below are from 17763) for use in Visual Studio 2019. Every time I try, the install hangs. I finally have to go into Task Manager and kill off several processes. There are usually three for <code>winsdksetup.exe</code> and one <code>Windows Installer</code>. </p>
  
  <p>I've tried installing from the Visual Studio Installer, and also from the standalone SDK installer. They all hang, even the full ISO download of the SDK. Installing it standalone (outside Visual Studio), it gets as far as "Updating Settings" (around 45%) and then just sits there. I've left it for hours. I go in and find the same dead processes.</p>
  
  <p>The logs, of course, are massive. A few relevant bits I've found are messages such as:</p>
  
  <pre><code>MSI (s) (84:D8) [11:40:21:462]: Warning: Local cached package 'C:\Windows\Installer\75742b.msi' is missing.
  MSI (s) (84:D8) [11:40:21:463]: SOURCEMGMT: Source is invalid due to missing/inaccessible package.
  MSI (s) (84:58) [11:43:33:684]: Product: Kits Configuration Installer -- Error 1714. The older version of Kits Configuration Installer cannot be removed.  Contact your technical support group.  System Error 1612.
  </code></pre>
  
  <p>It seems like something is missing or broken in my system... does anyone know what it could be, or how to fix this?</p>