diff --git a/win32ss/gdi/gdi32_vista/dc.c b/win32ss/gdi/gdi32_vista/dc.c
index c985aa22255b4..7068f8bf1e8a8 100644
--- a/win32ss/gdi/gdi32_vista/dc.c
+++ b/win32ss/gdi/gdi32_vista/dc.c
@@ -15,12 +15,12 @@
 /***********************************************************************
  *           D3DKMTCreateDCFromMemory    (GDI32.@)
  */
-DWORD WINAPI D3DKMTCreateDCFromMemory( D3DKMT_CREATEDCFROMMEMORY *desc )
+NTSTATUS APIENTRY D3DKMTCreateDCFromMemory(_Inout_ D3DKMT_CREATEDCFROMMEMORY* desc)
 {
     return NtGdiDdDDICreateDCFromMemory( desc );
 }
 
-DWORD WINAPI D3DKMTDestroyDCFromMemory( const D3DKMT_DESTROYDCFROMMEMORY *desc )
+NTSTATUS APIENTRY D3DKMTDestroyDCFromMemory(_In_ CONST D3DKMT_DESTROYDCFROMMEMORY* desc)
 {
     return NtGdiDdDDIDestroyDCFromMemory( desc );
 }