I try to turn off the call() to FreeLibrary() to Debug my leak, but it's little complicate to do it, because I have static object how make allocation with a memory manager (only for malloc and free, not for new and delete). So if I don't call the FreeLibrary the destructor off my static object is not call, and i have some crash when I free my memory manager. So for the moment, to debug leak, I remove the Freeliberary() and I don't release my memory manager to see the leak. But I hope to find an other solution without changing some code to with memory leak. My application and my DLL are compile in Debug with option "Multithread DLL"