You may need to take ownership of the files. Take a look here
for
the procedure:

How to take ownership of a file or folder in Windows XP
http://support.microsoft.com/default.aspx?scid=kb;en-us;308421

Note: If you are running Microsoft Windows XP Home Edition, you
must start the computer in safe mode, and then log on with an
account that has Administrative rights to have access to the
Security tab. To start in Safe Mode, reboot your computer and
start tapping the F8 key as soon as you see anything displayed
on the screen. Keep hitting F8 until the Advanced Startup
Options menu appears. Use the up and down arrow keys on your
keyboard to select Safe Mode. Hit Enter.

Good luck

Nepatsfan