>I have some .png files that I would like to include in my ASP project. For some reason, they are not showing up in the file browser window when I choose Add Existing Item. Any idea what the problem might be? I have checked multiple times to make sure that the files are in the folder where I'm looking for them.

I had to add some of those recently. They do appear in my environment. The default is *.*. So, if you have it set like that, all files in your folder should be available to be selected.