title: what is a #define _WIN32_DCOM a in visual c++ project?
body: <p>What is </p>
  
  <pre><code>#define _WIN32_DCOM
  </code></pre>
  
  <p>in a visual c++ project ? If I want to target the application build to x64, do I need to change it to WIN64_DCOM object ?</p>