I have had a reccuring DNS error on our SBS server for quite some time now. I’m not too sure how it came about but i suspect it was something to do with removing a member server that was acting as a second domain controller. The error was:
Event Type: Error
Event Source: DNS
Event Category: None
Event ID: 4000
Computer:Â Â Â SBS01
The DNS server was unable to open Active Directory.Â This DNS server is configured to obtain and use information from the directory for this zone and is unable to load the zone without it.Â Check that the Active Directory is functioning properly and reload the zone. The event data is the error code.
Long story short, i had a duplicate zone in my dns server that was empty – all i needed to do was remove it and restart a few service an hey! no error.
the zone was _msdcs under mydomain.com – it was greyed out with nothing inside it. I had another copy of thiszone above it called _msdcs.mydomain.com which had all the right data in it.
- So i deleted the empty _msdcs entry
- at a command propmt ran: net stop netlogon
- then: ipconfig /flushdns
- then restart the DNS server
- then run: net start netlogon
- and finish with: ipconfig /registerdns
No more error in 6 easy steps! 🙂