Thanks for the response. I've been out for more than a week, so it took me a while to get back to you.
Much to my suprise, my computer was upgraded to Office 2007 and I got a new cpu. The icon problem disappeared, because they used an earlier version of my desktop to load onto the new cpu.
However, since you asked, from File Explorer, I clicked on Tools/Folder Options/File Types, and then deleted the .ico extension (this was an accident). Then I added it back in, and it automatically picked a type of icon to display.