I have found your batch file via Google and tried it already. The problem remains. This started several months ago when I decided that I need a domain controller in my home and joined the domain. This PC is just on a workgroup now. I am told that this is pretty common when a computer detaches from a domain.
Brink, how about rebuilding the icon cache on this one or completely removing the arrow from the icon.
Are they showing that way in your start menu also ?