diff --git a/include/boost/smart_ptr/detail/lwm_win32_cs.hpp b/include/boost/smart_ptr/detail/lwm_win32_cs.hpp
index 9dfc2c6..9de2d65 100644
--- a/include/boost/smart_ptr/detail/lwm_win32_cs.hpp
+++ b/include/boost/smart_ptr/detail/lwm_win32_cs.hpp
@@ -44,10 +44,10 @@ struct critical_section
 #endif
 };
 
-#if BOOST_USE_WINAPI_VERSION < BOOST_WINAPI_VERSION_VISTA 
-extern "C" __declspec(dllimport) void __stdcall InitializeCriticalSection(critical_section *);
-#else
+#if BOOST_PLAT_WINDOWS_RUNTIME 
 extern "C" __declspec(dllimport) void __stdcall InitializeCriticalSectionEx(critical_section *, unsigned long, unsigned long);
+#else
+extern "C" __declspec(dllimport) void __stdcall InitializeCriticalSection(critical_section *);
 #endif
 extern "C" __declspec(dllimport) void __stdcall EnterCriticalSection(critical_section *);
 extern "C" __declspec(dllimport) void __stdcall LeaveCriticalSection(critical_section *);
@@ -72,10 +72,10 @@ public:
 
     lightweight_mutex()
     {
-#if BOOST_USE_WINAPI_VERSION < BOOST_WINAPI_VERSION_VISTA
-        InitializeCriticalSection(&cs_);
-#else
+#if BOOST_PLAT_WINDOWS_RUNTIME
         InitializeCriticalSectionEx(&cs_, 4000, 0);
+#else
+        InitializeCriticalSection(&cs_);
 #endif
     }
 
diff --git a/include/boost/smart_ptr/detail/yield_k.hpp b/include/boost/smart_ptr/detail/yield_k.hpp
index 686780a..9f4496b 100644
--- a/include/boost/smart_ptr/detail/yield_k.hpp
+++ b/include/boost/smart_ptr/detail/yield_k.hpp
@@ -59,7 +59,7 @@ namespace boost
 namespace detail
 {
 
-#if !defined( BOOST_USE_WINDOWS_H ) && BOOST_PLAT_WINDOWS_DESKTOP
+#if !defined( BOOST_USE_WINDOWS_H ) && !BOOST_PLAT_WINDOWS_RUNTIME
   extern "C" void __stdcall Sleep( unsigned long ms );
 #endif
 
@@ -74,7 +74,7 @@ inline void yield( unsigned k )
         BOOST_SMT_PAUSE
     }
 #endif
-#if BOOST_PLAT_WINDOWS_DESKTOP
+#if !BOOST_PLAT_WINDOWS_RUNTIME
     else if( k < 32 )
     {
         Sleep( 0 );