Ok, here is a new development, my main DC came back to life but it is no longer DC on the domain. Since it got a new computer name, instead of computer A now it computer B. I can not change the name back to A. Since, IP address is the same and DHCP is installed on this machine when it is on, users can connect to the network. Now, my new question is can I run DCPROMO in this machine to promote it as DC, with the existing DHCP and WINS setup on it. I know this machine is handling out ip address because when I turn it off no one can log-on.
Thanks,
Kevin Nguyen