CACLS command

I was getting an error with certain video files where the
computer thought they were in use when they were not.
Someone told me about simple file sharing in Windows XP,
and showed me how to use the CACLS command in the DOS
shell to change file permissions (since I can't disable
simple file sharing in Windows XP Home).

With some files though, even after using CACLS to change
the permissions to full, I cannot move, delete, or rename
the file. The cacls command I am using is:

cacls <directory> /e /t /g users:f

This command works on 99% of the files that I have the
problem with. After using it on this one file though, the
prompt tells me that the file has been processed, but I
still cannot access it in any way. Can someone please
shed some light on this for me?

Thank you.

~Dan
Dalokgawd@yahoo.com