I want to call a pure C style function from a dll in my C++ program. I tried casting my function pointer using reinterpret_cast to __cdecl and still the calling convention of _stdcall seems to be preserved. I am new to Windows C++ programming. This is my C++ call Code: reinterpret_cast< Error ( __cdecl*)(int,int)> (GetProcAddress(Mydll::GetInstance()->ReturnDLLInstance(), "add"))(1,10) actual function in the dll is Code: Error __cdecl add(int,int); Debugger throws me the error run time check failure #0. I am working in Windows-C++. Also I am exporting functions from my dll and I dont have access to my C files.