This security setting determines the number of days' worth of events to be retained for the security log if the retention method for the security log is By Days.
Set this value only if you archive the log at scheduled intervals and you make sure that the Maximum security log size is large enough to accommodate the interval.
This setting does not appear in the Local Computer Policy object.
A user must possess the Manage auditing and security log user right to access the security log.
Computer Configuration\Windows Settings\Security Settings\Event Log
Only Windows XP SP2, Windows Server 2003
Event Log security settings are not registry keys.