The message doesn't discuss my file at all. It leads me to think I have permission problems with my 'E' folder. Incredibly misleading when you find out what is really going on. If I refresh Windows Explorer's view of the folder (hit F5 or reopen Windows Explorer, etc.) I find that my old file is back! It wasn't deleted at all. And since the file is probably still in use, I am unable to replace it with my new file. How's that for strange behaviour?
(BTW, my team managed to create a silent install of Visual Studio 6 for SMS if anyone is interested. A very, very complicated procedure to say the least. I haven't been covering any scripting yet, but I can write an article on it if there is interest.)