Hello Rafael Silva,
Thank you for posting in Q&A forum.
Please try to troubleshoot the error above based on the following points:
1.How many Domain Controllers in your domain? You can check by running command:
netdom query dc
For example:
nltest /dclist:domain.com
For example (domain name is the actual domain name in your environment):
You can also check it via GUI on one domain controller.
2.Please check the AD replication by running commands below on PDC:
repadmin /showrepl >C:\rep1.txt
repadmin /replsum >C:\rep2.txt
repadmin /showrepl * /csv >c:\repsum.csv
3.Please ping the DNS name and IP of the DNS server and the FQDN of the DNS server on this problematic machine.
For example:
a.com is my domain name, the name of the domain controller is DCA and it is also a DNS server, the IP address of this Domain Controller (DNS server) is 10.32.168.5.
4.Please check the DNS setting on the server, make sure the preferred DNS server is the IP address of one active and running DNS server (DNS server usually is one Domain Controller).
Please run ipconfig /all on this machine to check the Preferred DNS server.
5.If the DNS setting on the server is point to one the IP address of one DNS server (DNS server usually is one Domain Controller) and this DNS server (DNS server usually is one Domain Controller) is removed from the domain, you should reset the DNS setting on the server using a new the IP address of one DNS server.
Here is a similar thread for your reference.
[https://learn.microsoft.com/en-us/answers/questions/1092189/ad-is-not-reachable-but-it-runs-(the-specified-dom](https://learn.microsoft.com/en-us/answers/questions/1092189/ad-is-not-reachable-but-it-runs-(the-specified-dom)
I hope the information above is helpful.
If you have any questions or concerns, please feel free to let us know.
Best Regards,
Daisy Zhou
============================================
If the Answer is helpful, please click "Accept Answer" and upvote it.