Figure this situation: lots of Active Directory and DNS related errors, DCDiag immediately returned error 81.
Solution: rebooting the server did the trick. You don’t have to be a rocket scientist to solve seemingly complex issues 😉
Of course this will not always solve errors 81, but it will probably not hurt to try a reboot first …
To find out if your PC is vunerable for the DNS bug discovered by Dan Kaminsky, check out http://www.doxpara.com/ and click on “Check My DNS”.
You’ll find more technical details about the DNS bug on the same page, or here: http://www.linuxjournal.com/content/understanding-kaminskys-dns-bug.
If you use a domain with single-label DNS name (for example mydomain instead of mydomain.net) – which is not recommended – you need to do some extra steps otherwise Win2000 or XP clients will not able to dynamically register DNS records.
For more info, see the following Microsoft article:
Information about configuring Windows for domains with single-label DNS names