And security can only be set in an NTFS partition. Security tab is available only to Administrator or users with administrative rights.
I tried plugging it in to said computer and it would be visible. So to see and unhide the Security tab, just use the following steps:
By default, Windows XP Professional follows recommended setting to enable the use of simple file sharing that hides the Security tab, leaving you with only General, Sharing, Web Sharing & Customize tabs as in the Simple File Sharing UI. Security tab for the properties of files or folders in Windows XP Professional is the important functionality that enable administrators and users to define security permissions and rights for particular user or group to the computer resources.