Debugging is very important element in programming development. We can find a lot of bug of program we made, and we can fix it. but after a product is released, we need system we can catch bugs as soon as possible. For this, we need to know post-mortem debugging. We will look at post-mortem debugging, and we will talk about process dump. Also when process get the problem, we should get the process dump, but we can have situation process dump was not generated. We will consider this case, and we will examine programming technique which this case can be retrieved. Finally, I will introduce EHModule(exception handler module)