File Rights Security question

Archived from groups: microsoft.public.windowsxp.security_admin (More info?)

I've got a strange situation that I'm not able to explain. A user account is
able to write a file to a folder they don't have Write access to.

I have a folder off the root directory that I created using an account,
userA - C:\DUMP
I then removed the Everyone group from the root, and reassigned the rights
to the folder such that the only access rights upon it are for
Administators, System and Users. With Users only have List access. UserA was
then made a member of the Users group only - having formerly been an
Administrator.
I logged out, and then back in as UserA, and found that this user could
create files within the folder I'd just created, but not delete them. Why is
this ?

The PC is not a member of a Domain, so only local accounts are being used.

Any ideas ?

Regards in advance.


Steve