Crash after m = XMMatrixIdentity() - alignment memory in classes?

Question

I was looking at the tutorials in DirectX SDK. Tutorial 5 works fine, but after I have copied and separated the code to my own classes, I got strange error during launching

Answer 1

In the Book "Introduction to 3D Game Programming with Directx 11" from "Frank D. Luna" it says:

Do not use XMMATRIX as Member of a class or Structure. Always use XMFloat4x4 and load and store back if you need it.