There are a lot of image files in a folder and the view is set to thumbnails.There are several possibilities and the green bar can appear when: The question is, what can it be busy doing? It is performing a task that is taking a long time and so it shows a green bar so that you can see its progress. The green bar is Explorer’s way of indicating that it is busy doing something. What is going on and how can it be stopped? This can happen occasionally to everyone, but to some people it is a constant irritation. Here is the reason and how to minimise it. When opening an Explorer window you sometimes have to wait while a green bar very slowly works its way across the address box at the top.
