I had a project using both native and CLR code C++.Net. I added serialization to it. Its just crashing. I checked RTTI IS enabled.. I had this problem earlier. I had split the serialization function to both .h and .cpp files. Then it disappered when I wrote it in the class declaration in the .h file. But after I did the same to all the classes (almost 20) that needed serialization. It compiles fine, but crashes even before starting.. Debug information ============= //below the msg box that appears --------------------------- Microsoft Visual C++ Debug Library --------------------------- Debug Assertion Failed! Program: g:\Development\R50\Debug\New Rapid Vision.exe File: f:\dd\vctools\crt_bld\self_x86\crt\src\dbgheap.c Line: 1511 Expression: _CrtIsValidHeapPointer(pUserData) For information on how your program can cause an assertion failure, see the Visual C++ documentation on asserts. (Press Retry to debug the application) --------------------------- Abort Retry Ignore --------------------------- //stack trace msvcr90d.dll!_msize_dbg(void * pUserData=0xdc9ffce0, int nBlockUse=2) Line 1511 + 0x30 bytes C++ msvcr90d.dll!_dllonexit_nolock(int (void)* func=0xdcd983c0, void (void)* * * pbegin=0x0012eecc, void (void)* * * pend=0x0012eec4) Line 295 + 0xd bytes C msvcr90d.dll!__dllonexit(int (void)* func=0xdcd983c0, void (void)* * * pbegin=0x0012eecc, void (void)* * * pend=0x0012eec4) Line 273 + 0x11 bytes C New Rapid Vision.exe!_onexit(int (void)* func=0x00467f20) Line 110 + 0x1b bytes C New Rapid Vision.exe!atexit(void (void)* func=0x00467f20) Line 127 + 0x9 bytes C New Rapid Vision.exe!boost::serialization::singleton<boost::archive::detail::`anonymous namespace'::oserializer_map<boost::archive::xml_oarchive> >::get_instance() Line 104 + 0x34 bytes C++ New Rapid Vision.exe!`dynamic initializer for 'boost::serialization::singleton<boost::archive::detail::`anonymous namespace'::oserializer_map<boost::archive::xml_oarchive> >::instance''() Line 121 + 0x8 bytes C++ [Managed to Native Transition] New Rapid Vision.exe!_initterm(void** pfbegin = 0x004683C4, void pfend = ) Line 130 C++ New Rapid Vision.exe!<CrtImplementationDetails>::LanguageSupport::InitializeNative() Line 534 C++ New Rapid Vision.exe!<CrtImplementationDetails>::LanguageSupport::_Initialize() Line 657 C++ New Rapid Vision.exe!<CrtImplementationDetails>::LanguageSupport::Initialize() Line 855 C++ New Rapid Vision.exe!?.cctor@@$$FYMXXZ() Line 901 + 0x9 bytes C++ [Frames below may be incorrect and/or missing, no symbols loaded for mscorwks.dll] kernel32.dll!7c83971e() kernel32.dll!7c809a69() kernel32.dll!7c83971e() kernel32.dll!7c809a69() mscoree.dll!7900b1b3() kernel32.dll!7c816fd7() -- With best Regards Rajavanya S Twitter me @ https://twitter.com/quakeboy I Blog @ http://www.techtola.com Call me @ 9916-90-93-92 ---------------------------------------------------------------------------------------------- "True love is knowing a person's faults, And loving them even more for them."