The security tab for the file property disappears in certain Windows XP installations. Here is how to display the security tab
To display the Security tab
Open Folder Options in Control Panel. (Click Start, click Control Panel, click Appearance and Themes, and then click Folder Options.)
On the View tab, under Advanced settings, clear the Use simple file sharing [Recommended] check box.
By using the access control feature available in Windows XP Professional, you can help ensure that only the people you want to access the files and folders on your network are able to get to them