I am working on a Active Directory migration project from Windows 2003 R2 Active Directory to 2008 R2 Active Directory fir multiple sites.
After I completed my migration project I was noticed that below error whenever I was trying to add a PC/laptop/Server to the domain, but it successfully adds to the domain.
But this error is very critical because when we add a duplicate name it won't give us the duplicate name errors simply it over-writes the existing host name which makes lot of issues.
I faced this critical error which makes over-writes the host names in the domain when you join.
For example: Already you had a host name called as PC.domain.com in the domain.com Domain.
When you try to add the another host name called as PC in the domain.com Domain, it doesn't give you the duplicate name error on the network it does over-write the existing host name called as PC.domain.com & it will add the new host name into the domain.
Host name which got over-written will get removed from the domain. I faced this issue in my project. My DPM host name got removed from the Domain & new host name got joined into the domain which halted my backups for one day.
Final Resolution is as follows:
You need to start the dns console on the DC & drop down the domain name.
Select the _msdcs when you click on _msdcs it will show the Name Server's list on the right hand side.
You need to add the Domain Naming Master under the _msdcs or add all the domain controllers which you had.
After you add the Name server's try joining the PC OR Laptop OR Server to the domain which is successfully joins it.
I hope this will resolve your issue.
NOTE : If this posts helpful to resolve your issue, please comment.