Sometimes bad things happen, sometimes ugly things happen. One of the very bad things that can happen is when an active domain controller crashes and there is no backup available. The case becomes really ugly if nobody cares about the crashed controller for about 60 days (forest that was created on a domain controller running Windows Server 2003 and earlier) or 180 days (forest that was created on a domain controller running Windows Server 2003 sp1 and later). On this depends the default...
Kick the crashed AD controller out
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