title: When does #if WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP) in dxvahd.h Microsoft header file become true
body: <p>Hi I am having 2 VC++ solutions "A" &amp; "B" (VS2008) both are having the same codebase (with just few lines of code different). Using DXVAHD.h in both.</p>
  
  <p>dxvahd.h is a standard Microsoft header file. If we open this header file, we see there is a conditional if 
  "<code>#if WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP)</code>"</p>
  
  <blockquote>
    <p>I see that in VC++ solution "A", the above conditional #if statement
    is false, hence the whole dxvahd header file gets greyed out &amp; is not
    even compiled!!</p>
  </blockquote>
  
  <p>Whereas in another solution "B", this conditional #if is true,hence no issues &amp; its working fine.</p>
  
  <p><strong>Can anyone kindly let me know how do I resolve this issue in solution "A", wherein the above #if is getting greyed out / not compiling. PLz help me.</strong></p>
  
  <p>Thanks in advance.</p>