Hacker put files in directories I can't look at and I can't delete the files.

From: Nick Messick (nick@trendwhore.com)
Date: 03/16/02

From: nick@trendwhore.com (Nick Messick)
Date: 15 Mar 2002 15:07:52 -0800

A hacker anonymously ftp into one of my machines and dump a bunch of
files. The directories have weird names so I went to the DOS promt
and I was able to get rid of most of the files and most of the
directories. The problem is a few of the files say "Access is denied"
when i try to delete them using del *.* /f. How can I make these
files accessible so I can delete them?