Unattended Windows 7 install with non-DHCP DNS Server: Domain join fails, claiming it can't find the domain
Solution 1:
There are a couple of options to help you join your machines to the domain in this situation.
First, because the network settings are being set in the specialize pass, you can run a script later in the process that joins the computer to the domain. In the oobesystem pass, you can use the ‘SynchronousCommand’ settings under the ‘FirstLogonCommands’ setting which is part of the Microsoft-Windows-Shell-Setup component to run a script to join the computer to the domain.
Another option is to use Offline Domain Join as explained in this TechNet article: ‘Offline Domain Join (Djoin.exe) Step-by-Step Guide’ .
More Step-by-Step guides and videos to help with your deployment needs can be found on the Deliver and Deploy Windows 7 and the Deliver and Deploy Windows 8 pages of the Springboard Series on TechNet.
Hope this helps,