Server 2012 R2 DHCP authentication error (1046-DHCP)

Question

Hello all, here is my story, hope someone can help me solve it.
Goal :
Getting the DHCP running on windows server 2012 R2
Current situation :
We have two different domains in one forest (domain-A & domain-B).
Domain-A has several w2k8r2 servers. In Domain-A we have two server 2008 R2 domain controllers (serverA1 & serverA2). On both servers the DHCP rule is installed and running.
Domain-B has several w2k8r2 servers. In Domain-B we have two server 2008 R2 domain controllers. Both servers don’t have DHCP server role !
We installed 2 w2k12R2 servers (server-b1 & server-b2)  in domain-B and promoted to domain controller. We installed the DHCP server role on server-b1 & server-b2 configured the failover. The domain function lever is still w2k8r2.
The change :
In domain-A we unauthorized the DHCP server-A1 & server-A2 and deleted the DHCP server role.
Restarted server–A1 & server-A2 and checked if the DHCP server role is removed.
In domain-B we restarted server-B1 & server-B2. We authorized the DHCP on server-B1 & server-B2.
The error :
The DHCP didn’t go online, it gives the following error message in the event viewer (this is the only error message about the DHCP server)
Eventid 1046, DHCP-Server
The DHCP/BINL service on the local machine, belonging to the Windows Administrative domain Domain-B, has determined that it is not authorized to start. 
It has stopped servicing clients.  The following are some possible reasons for this:
This machine is part of a directory service enterprise and is not authorized in the same domain. 
(See help on the DHCP Service Management Tool for additional information).
This machine cannot reach its directory service enterprise and it has encountered another DHCP service on the network belonging to
a directory service enterprise on which the local machine is not authorized.
Some unexpected network error occurred.
Tried solutions :
1) checked the local network settings, the dns server is the one in the old forest (domain-A) this is correct !
2) Checked with adsiedit.msc if there was still an entry that was looking at server-A1 & server-A2. Nothing found. 3) I unauthorized the 2 new servers (server-b1 and server-b2) I installed a new w2k12R2 server in domain-A1, installed the dhcp server role
only. Tried to authorizes the dhcp server but the exact same error.
looking forward to all the ideas, and the solution
J
Design is the Technology

Answer 1

Hi,
According to your description, when we installed a new windows server 2012 r2 in the domain A and only installed the DHCP role, the authorization was still not success. So please check if the unauthorized and authorized process was success. To verify if
the DHCP servers have been authorized, please try to run netsh dhcp show server
command, then we can see the DHCP server which was authorized. And you mentioned that you have checked with ADSIEdit to see if there was an entry. Yes, we can make full use of ADSIEdit. If a DHCP server was authorized successfully, there must be an
entry about the DHCP server in the ADSIEdit. So please check if there are some entries in the ADSIEdit of all your DCs in the domain. Ensure that only one entry about this new windows server 2012 r2 in the ADSIEdit.
If there are different in the several DCs, please try to use AD replication to make the data consistent.
And we must log on the server as an administrator to complete this operation.
To check the entry, please follow steps below,
1. Start adsiedit.msc.
2. Open the Configuration container.
3. Expand Services.
4. Expand Net Services.
Best Regards,
Tina