Question : DNS  problem event ID 4515 the zone (mydomain) was previously loaded..

hello, i am getting this error on my event log and i cant figure out why...

here is what the message says

The zone (mydomain).local was previously loaded from the directory partition MicrosoftDNS but another copy of the zone has been found in directory partition DomainDnsZones.(mydomain).local. The DNS Server will ignore this new copy of the zone. Please resolve this conflict as soon as possible.
 
If an administrator has moved this zone from one directory partition to another this may be a harmless transient condition. In this case, no action is necessary. The deletion of the original copy of the zone should soon replicate to this server.
 
If there are two copies of this zone in two different directory partitions but this is not a transient caused by a zone move operation then one of these copies should be deleted as soon as possible to resolve this conflict.
 
To change the replication scope of an application directory partition containing DNS zones and for more details on storing DNS zones in the application directory partitions, please see Help and Support.

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.

Answer : DNS  problem event ID 4515 the zone (mydomain) was previously loaded..

> I saw the link, but how can I determine which Zone I want to delete?

Open the DNS Console, right click on the existing forward lookup zone and check the Properties.

These are the combinations:

All Domain Controllers in the AD Domain = Domain partition (as seen in AD Users and Computers under the System\MicrosoftDNS folder)
All DNS Servers in the AD Domain = DomainDNSZones
All DNS Servers in the AD Forest = ForestDNSZones

Once you know where your active copy is loading from you can be pretty sure any copy in either of the other two is a problem. If you find one it can be safely deleted. If you would prefer explicit instructions for that then don't hesitate to ask.

> What would be the consequences of removing the wrong one ?

Actually fairly limited. You lose the contents of your forward lookup zone (as seen in the DNS console). But the majority of that is dynamically registered so will quickly repopulate. It can be annoying if you have a lot of manually configured records though.

Chris