Why doesn't Visual Studio refresh the folders when I click the Solution Explorer refresh button?

Question

In Visual Studio 2008, I can see all my project files in my Solution Explorer, and these files exist in an actual diectory.

However, if I add a file to that directory

Answer 1

On the solution, click the right mouse button and select 'Add existing item' and pick the file from the solution root directory. The Solution will now get a 'Solution Items' directory which contains your file. This directory is virtual, so it does not exist on disk.

However there is no feature like 'Show All Files' for a solution, this only works on projects.