Hi

 

 If this is a single domain in a forest, then just demoting should be good.Do you have other zones that were delegated to this domain/zone?If you want to manually remove this zone, you should just be able to go to the parent zone and delete the NS and A records for this zone.

If you are unsure if you have any type of issues.This will detail out any problems you aren't aware of.
http://blogs.dirteam.com/blogs/paulbergson/archive/2009/01/26/troubleshooting-active-directory-issues.aspx

This is the error that I got during domain controller removal on windows server 2008. It says the zone is a period (.)? The domain controller demoted successfully with the dcpromo wizard. I checked the other dcs in the domain and everything looked fine except for DNS. I just had to delete DNS references to the demoted server in DNS.

This is the error that I got during domain controller demotion. Is it safe to ignore?
---------------------------
Active Directory Domain Services Installation Wizard
---------------------------
DCPromo was unable to remove DNS delegations from the parent zone: .. This could be because you do not have permissions to do so, or because the zone is hosted by a server that does not run Windows. You should delete DNS delegations in the parent zone for this domain. To do so, contact an administrator who is responsible for the DNS zone: ..
The error was:

The RPC server is unavailable.
---------------------------
OK   
---------------------------

Thanks

Hi

Please refer below thread on similar discussion,
http://community.spiceworks.com/topic/362726-demoting-a-dc?page=1#entry-2

Hi

 

 If this is a single domain in a forest, then just demoting should be good.Do you have other zones that were delegated to this domain/zone?If you want to manually remove this zone, you should just be able to go to the parent zone and delete the NS and A records for this zone.

If you are unsure if you have any type of issues.This will detail out any problems you aren't aware of.
http://blogs.dirteam.com/blogs/paulbergson/archive/2009/01/26/troubleshooting-active-directory-issues.aspx

"DCPromo was unable to remove DNS delegations from the parent zone: .."

This is a single domain in a forest. I have deleted the NS and A records in the parent zone and AD is working fine.

Why does DCPromo say the parent zone is a dot(.)? I don't have any zones that are just a dot(.). Shouldn't it say something like .com?

Thanks

Hi

 Just make sure none of your other DNS servers are using this demoted server as a forwarder or secondary server,maybe cause of this.

Hi,

Can you check the entry on below location if any kindly delete the  same.

Dnsmgmt.msc [Dns Management]
 A.Expand the forward lookup zones\_msdcs folder
 i. Make sure only the actual domain controllers are listed, delete wrong Alias recordsremove wrong name server records
 ii. Select the container [forward lookup zones\_msdcs.domain.com\dc\_sites_\sitename\_tcp] > delete incorrect _ldap and _kerberos records are listed.
 iii. Select the container [forward lookup zones\_msdcs.domain.com\dc\_tcp] and delete incorrect _ldap and _kerberos records
 iv. Expand the [forward lookup zones\_msdcs.domain.com\domains\guid\_tcp] and delete incorrect _ldap entries
 v. Select [forward lookup zones\_msdcs.domain.com\gc] delete incorrect HostA records
 vi. Expand the [forward lookup zones\_msdcs.domain.com\gc\_sites\sitename\_tcp] delete incorrect _ldap entries
 vii.Select the [forward lookup zones\_msdcs.domain.com\gc\_tcp] delete incorrect _ldap entries
 viii. Select the [forward lookup zones\_msdcs.domain.com\pdc\_tcp] delete incorrect _ldap entries
 
 B.Expand the forward lookup zones\domain.com folder
 i.Delete Host(A) records of dcs which are non-existant.
 ii.Correct the NameServer (NS) records
 iii. Follow steps similar to A ii >> A viii
 
Dssite.msc [Sites and Services]
 A.Expand the [Sites\Sitename\Servers] delete incorrect servers
 B.Delete incorrect subnet configurations [Sites\Subnets]
 C.Delete incorrect site links [Sites\IP]
 
  Make sure the domain controllers are pointing to the correct dns servers in tcp\ip settings.
  Force replication repadmin /syncall