Hacker "scanned" my webserver

From: Dr. Bob (anonymous_at_discussions.microsoft.com)
Date: 05/10/04 

Date: Mon, 10 May 2004 07:56:07 -0700

I have a Win2K webserver running IIS that was "scanned" by a hacker. I now have files/folders with non-printing characters in their names. When I try to delete them, I get "file not found" or "cannot read from source file or disk" errors. Any way to fix this problem? Also, what can I do to keep this from happening again? Thanks for your help.
Bob