diff --git a/sdk/include/psdk/ddraw.h b/sdk/include/psdk/ddraw.h
index 637afd9e280..a7d01b54363 100644
--- a/sdk/include/psdk/ddraw.h
+++ b/sdk/include/psdk/ddraw.h
@@ -8,7 +8,9 @@
 #else
 #define IUnknown void
 #if !defined(NT_BUILD_ENVIRONMENT) && !defined(WINNT)
-        #define CO_E_NOTINITIALIZED 0x800401F0L
+  #ifndef CO_E_NOTINITIALIZED /* Avoid conflict warning with _HRESULT_TYPEDEF_(0x800401F0L) in winerror.h */
+  #define CO_E_NOTINITIALIZED 0x800401F0L
+  #endif
 #endif
 #endif