To do this, you must be running NTFS as your file system on the drive in
question. If your hard disk/partition is not NTFS you will need to convert
it. To do this, open a Command Prompt window and enter the following
command:
CONVERT X: /FS:NTFS
Where X: is the drive letter you wish to convert. You may also want to see
http://www.aumha.org/a/ntfscvt.htm to ensure that you're getting the optimal
conversion.
After this step is completed and you've rebooted the computer, if necessary:
XP PRO: In Windows Explorer, go to Tools, Folder Options, View and uncheck
Use Simple File Sharing. Now, when you right click on a drive, folder or
file (on an NTFS partition) and select Properties, you'll see a Security
tab. Here you can assign or deny permissions based on user name or user
group membership.
XP Home: By default, you can only make files and folders under My Documents
"private". This is done by right clicking a folder or file and selecting
Properties, Sharing. To change the permissions on other folders, you need
to boot the computer to Safe Mode and log in on the built in Administrator
account. In this mode, you'll see the Security tab in Properties, and you
can assign permissions based on user name or group membership.
How Do I Get the Security Tab in Properties - XP Home (makes the Security
tab appear outside of Safe Mode)
http://www.dougknox.com, Win XP Tips section
HOW TO: Set, View, Change, or Remove File and Folder Permissions in Windows
XP
http://support.microsoft.com/default.aspx?scid=kb;en-us;308418
HOW TO: Set, View, Change, or Remove Special Permissions for Files and
Folders
http://support.microsoft.com/default.aspx?scid=kb;EN-US;308419
HOW TO: Disable Simplified Sharing and Password-Protect a Shared Folder in
Windows XP
http://support.microsoft.com/default.aspx?scid=kb;EN-US;307874