Hello I can't compile my simple project for serializing shared_ptr . I read the archives and google it and still can't compile it :) I am doing the following : /////A.h #pragma once #include <boost/archive/xml_iarchive.hpp> #include <boost/archive/xml_oarchive.hpp> #include <boost/serialization/nvp.hpp> #include <boost/serialization/shared_ptr.hpp> class A { public: A(int k):mk(k) { } A() { } template<class Archive> void save(Archive & ar, const unsigned int version) const { using boost::serialization::make_nvp; ar & BOOST_SERIALIZATION_NVP(mk); } template<class Archive> void load(Archive & ar, const unsigned int version) { using boost::serialization::make_nvp; ar & BOOST_SERIALIZATION_NVP(mk); } BOOST_SERIALIZATION_SPLIT_MEMBER() int mk; }; BOOST_SERIALIZATION_SHARED_PTR(A) ///func.cpp #include "A.h" void func() { std::ofstream ofs(L"C:\\boostarchiveSharedPtr.xml"); std::ifstream ifs(L"C:\\boostarchiveSharedPtr.xml"); boost::shared_ptr<A> bPtr(new A(13)); { using boost::serialization::make_nvp; boost::archive::xml_oarchive oa(ofs); oa & BOOST_SERIALIZATION_NVP(bPtr); } boost::shared_ptr<A> rbPtr; { using boost::serialization::make_nvp; boost::archive::xml_iarchive ia(ifs); ia & BOOST_SERIALIZATION_NVP(rbPtr); } } And I am getting the following compile time error : 'boost::mpl::assertion_failed' : cannot convert parameter 1 from 'boost::mpl::failed ************boost::serialization::is_wrapper<T>::* ***********' to 'boost::mpl::assert<false>::type' D:\main\dev\sdk\libs\boost\inc\boost-1_38\boost\archive\basic_xml_oarchive.hpp 88 The comment about the erroir says : // If your program fails to compile here, its most likely due to // not specifying an nvp wrapper around the variable to // be serialized. I can't understand what does it mean, since I have BOOST_SERIALIZATION_NVP when writing /reading to the archive