I recently setup a new domain for a client. Everything was going well, and we were ready to start adding the machines to the domain.
Everything went without a hitch until a Vista machine was coming back with “An Active directory Domain controller for the domain domain.dom could not be contacted.”
So, my first thoughts, it’s gotta be a DNS issue. But, The machine was getting an address, DHCP, as every other machine was. Nslookup was working fine and I could find the FQDN of the server. Am I logged in as admin, yep. Is the windows firewall off, yep.
I gave the machine a static IP, with one DNS server, the DC, but still no joy. I added in the domain suffix and yet again, the same error.
I rebooted the server, checked all the logs, screamed a few times and then after some random clicking spotted that AVG was installed. Open AVG, click, disable firewall, click.
Can I now join the domain please, yep.
So, if you get this error and you’re sure everything is ok, look for a hidden firewall running on the local machine!