I took a look at this and it made no sense to me. I couldn't compile it as it needed a file QString to compile. I did have occasion to look into the code and Its not obvious to me what your intention here. It looks like you're trying to store class id information into the archive so that the proper class can be reconstructed. But that can't be it as the serialization library already does that. Also I notice that you're using extended_type_info_typeid as well as extended_type_info_no_rtti. This is very odd to me as I would expect that one's environment either has rtti enable or it doesn't. so I would expect either one or the other but not both. Anyway, sorrty I couldn't be more help. Robert Ramey "RIVASSEAU Jean Noel" <JN.RIVASSEAU@oberthurcs.com> wrote in message news:87F60F7FA02FF749AFB02BD9FCAA6B04DA7ABF@naserv31.nanterre.oberthurcs.com... Hello This is my last problem with the BSL but the most important one (because there is no workaround). I am trying to serialize a class (whose name is "ClassSpecification") which has a std::vector of pointers. The code for serializing the class the pointer refer to (MemberVariableSpecification) is written and instantiated correctly. However I cannot correctly serialize the std::vector. It fails with a message complaining about: C:/Boost/include/boost-1_33_1/boost/archive/detail/iserializer.hpp:115: error: incomplete type `boost::serialization::extended_type_info_null<std::vector<MemberVariableSpecification*, std::allocator<MemberVariableSpecification*> > >' used in nested name specifier I do not understand why I need an extended_type_info for this vector. I sure need it for the class the pointers refer to (and I did specify it), but the std::vector itself is serialized as such, not as a pointer. Why do I get this error ??? Can you please check the attached code and help me? Thanks Jean-Noël Ps: using gcc 3.4.2 _______________________________________________ Boost-users mailing list Boost-users@lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users