Review NTFS Permissions on All Data Directories
Tinkering with NTFS permissions is a tricky business. Unless you fully understand how these permissions work (including how permissions are inherited from higher-level folders and how permissions are transferred when folders or files are moved or copied), you should be wary of changing any permissions. In general, follow these guidelines whenever possible:

Use default storage locations. Install programs in subfolders under the Program Files folder and store personal data in the My Documents folder; in both cases, Windows applies a known set of permissions that you can tighten if necessary. If you have data files that are stored outside the default locations, consider moving them.
On Windows XP installations that are not joined to a domain, use the Simple File Sharing interface and the Network Setup Wizard to establish a baseline set of file and folder permissions. Afterward, you can modify these permissions as needed.
Test the effect of permissions by trying to access protected files from a limited account. Create a limited local account (Windows XP) or an account in the Users group (Windows 2000), log on with that account, and try to access files in the protected locations. (Be sure to eliminate or disable the test accounts when you're finished!)
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Go back to square one

If you (or someone else) has experimented extensively with the default permissions on an existing Windows installation and you're not confident that system and data files are properly protected, you can use a security template to reapply the default permissions to your computer. This procedure is fully documented in Knowledge Base article Q266118, "How to Restore the Default NTFS Permissions for Windows 2000." We discuss the Security Configuration And Analysis snap-in and the built-in Windows security templates in Using Security Templates.

Libellés : Data, Directories, NTFS, Permissions, Review