Hi I am using boost 1.49. I have custom archives derived from the boost binary archives. However it seems that when using BOOST_CLASS_EXPORT_GUID the types are not actually registered for the custom archive types, and I am getting unregistered_class exception when serializing derived class from base pointer. If I am using the boost binary original archives this is not the case. My custom archive classes are defined in in its own header file and at the end of the file I am including BOOST_SERIALIZATION_REGISTER_ARCHIVE, according to this in the documentation : " The newly created archive will usually be stored in its own header module. All that is necessary is to include the header and construct an instance of the new archive. EXCEPT for one special case. Instances of a derived class are serialized through a base class pointer. Such instances are not "registered" neither implicitly nor explicitly. That is, the macro BOOT_CLASS_EXPORT is used to instantiate the serialization code for the included archives. To make this work, the following should be included after the archive class definition. #define BOOST_SERIALIZATION_REGISTER_ARCHIVE(Archive) Failure to do this will not inhibit the program from compiling, linking and executing properly - except in one case. If an instance of a derived class is serialized through a pointer to its base class, the program will throw an unregistered_class exception." here is my archive h file : ------------------- customarchive.h -------------------- #include #include #include #include #include class CloneBinaryIArchive : // don't derive from binary_oarchive !!! public boost::archive::binary_iarchive_impl< CloneBinaryIArchive, std::istream::char_type, std::istream::traits_type >, public boost::archive::detail::shared_ptr_helper { typedef CloneBinaryIArchive derived_t; typedef boost::archive::binary_iarchive_impl< CloneBinaryIArchive, std::istream::char_type, std::istream::traits_type > base_t; public: CloneBinaryIArchive(std::istream & is,unsigned int flags = 0) : base_t(is, flags) {} CloneBinaryIArchive(std::streambuf & bsb, unsigned int flags = 0) : base_t(bsb, flags) {} int foo; }; BOOST_SERIALIZATION_REGISTER_ARCHIVE(CloneBinaryIArchive) and here is the cpp file in each I am registering all classes : -------------- register.cpp --------------- #include "customarchive.h" #include #include "A.h" BOOST_CLASS_EXPORT_GUID(A,"A") -- View this message in context: http://boost.2283326.n4.nabble.com/BOOST-CLASS-EXPORT-GUID-with-custom-archi... Sent from the Boost - Users mailing list archive at Nabble.com.