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"Access to machine resources when a domain controller is unavailable.
After a successful domain logon, a form of the logon information is cached. Later, a user can log on to the computer by using the domain account, even if the domain controller that authenticated the user is unavailable. Because the user has already been authenticated, Windows uses the cached credentials to log the user on locally. For example, suppose a mobile user uses a domain account to log on to a laptop that is joined to a domain. Then, the user takes the laptop to a location where the domain is unavailable. In this scenario, Windows uses the cached credentials from the last logon to log the user on locally and to allocate access to local computer resources."
Level 1 Support Technician