diff --git a/include/msxml2.idl b/include/msxml2.idl
index 452338bb01d..916e0e8ab3d 100644
--- a/include/msxml2.idl
+++ b/include/msxml2.idl
@@ -31,6 +31,10 @@ import "oaidl.idl";
 #define vi_progid(str)
 #endif
 
+cpp_quote("#ifdef __ISAXXMLReader_INTERFACE_DEFINED__")
+cpp_quote("#undef __MSXML2_LIBRARY_DEFINED__")
+cpp_quote("#endif")
+
 [
     uuid(f5078f18-c551-11d3-89b9-0000f81fe221),
     version(3.0),
diff --git a/include/msxml6.idl b/include/msxml6.idl
index 113704d5dbe..5bfb21d04ae 100644
--- a/include/msxml6.idl
+++ b/include/msxml6.idl
@@ -99,6 +99,10 @@ interface ISchemaAny;
 interface ISchemaIdentityConstraint;
 interface ISchemaNotation;
 
+cpp_quote("#ifdef __ISAXXMLReader_INTERFACE_DEFINED__")
+cpp_quote("#undef __MSXML2_LIBRARY_DEFINED__")
+cpp_quote("#endif")
+
 cpp_quote("#ifndef __MSXML_DOMNODETYPE_DEFINED")
 cpp_quote("#define __MSXML_DOMNODETYPE_DEFINED")
 typedef enum tagDOMNodeType