Dan said:
How do I turn off auto shut down of word when not in use
There is no such feature built into Word. I can leave Word running in the
background all day and nothing happens to it.
You may have an add-in that's causing this behavior, or if you're on a
corporate network your IT folks may have put something on your machine.
Another possibility is that you might have a corrupted document or template.
Even then, just leaving Word unused doesn't usually cause a shutdown.