Sysvol

Many people may overlook this very important folder. By default, Windows 2003 Server gives "authenticated users" full control of this folder. Patches will automatically adjust the security settings to accommodate for it, but you can easily do it yourself after installation of a new 2003 server machine.

The System Volume (Sysvol) is a shared directory that stores the server copy of the domain's public files that must be shared for common access and replication throughout a domain. The Sysvol folder on a domain controller contains the following items:

• Net Logon shares. These typically host logon scripts and policy objects for network client computers.
• User logon scripts for domains where the administrator uses Active Directory Users and Computers.
• Windows Group Policy.
• File replication service (FRS) staging folder and files that must be available and synchronized between domain controllers.
• File system junctions.

Best Practices for Sysvol Maintenance
http://support.microsoft.com/kb/324175

Authenticated Users Group Has Too Many Permissions to the SYSVOL Network Share
http://support.microsoft.com/kb/812538