I'd do what Jared said because I just set up an environment with the exact same directory structure and file name, copy and pasted your script, and ran it and it does exactly what it's supposed to do.
I'm at a loss at this point. The only things I can think of is that there's some sort of permission deal with one of the folders that TestComplete is not allowed access to alter it. Either that, or you have one of the files still locked as open, especially if it has been edited and altered by TestComplete and then not closed by TestComplete.
Sorry, not much help from here.
