diff --git a/include/reactos/idl/CMakeLists.txt b/include/reactos/idl/CMakeLists.txt
index 092a73bd856..b5857b99afe 100644
--- a/include/reactos/idl/CMakeLists.txt
+++ b/include/reactos/idl/CMakeLists.txt
@@ -8,8 +8,6 @@ list(APPEND SOURCE
     wlansvc.idl)
 
 MACRO_IDL_FILES(${SOURCE})
-remove_definitions(-DWINNT=0x502)
-add_definitions(-DWINNT=0x600)
 remove_definitions(-D_WIN32_WINNT=0x502)
 add_definitions(-D_WIN32_WINNT=0x600)
 MACRO_IDL_FILES(pnp.idl)