A healthy Active Directory and properly functioning Group Policy operations are critical to security for domain computers and users. A large number of security operations in every domain rely on them. Among the security functions of Active Directory, Group Policy, and their related services are
Authentication. The AD database stores user, group, and computer accounts and passwords.
The netlogon service is part of the authentication process. If net-logon fails, authentication fails.
Special operational roles, such as the PDC emulator, are critical. If the PDC emulator is not available in the domain, account lockout is possible, and time synchronization may not occur. If the RID master is unavailable and ...