Event ID - 4521

Event Id4521
SourceDNS
DescriptionThe DNS server encountered error 9002 attempting to load zone . from Active Directory. The DNS server will attempt to load this zone again on the next timeout cycle.
Event InformationAccording to News Group :
Error: 32 - The solution in my case was to configure the "DHCP Client" service to "Automatic".
A more accurate command than the one stated by Jim Raf is:“dnscmd /config /bootmethod [0|1|2|3]” , where 3 is default, i.e. boot from AD and registry.
If the zone is “.” and you do not have this zone, then try to create AD integrated “.” zone, convert it to non-AD integrated, and then delete zone “.”.I had these errors on some Windows 2003 DCs after applying SP2. These DCs were some years ago Windows 2000 DCs.
In my case, running "dnscmd /config /bootmethod" solved this problem.
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