This one is driving me crazy, I can't find an answer anywhere, but maybe I'm not looking correctly.
I'm promoting a Server 2008 SP2 box as a 2nd DC in a domain that is part of a larger forest. The DC promotion works fine, AD installs, DNS works ok, shares are good, printers work. I install DHCP, restart, login as an enterprise admin and authorize the DHCP server. Once I restart the server after that, I am unable to login as any administrator account to the DC. The only account that works is "administrator", my admin account doesn't work. The error I get is "Invalid username or password". I am able to login to the original DC with my admin account.
Looking through the event viewer, it looks like after authorizing the DHCP server and restarting, the new DC can't find a global catalog and fails all logins. If I unauthorize the DHCP server and restart, I can login as my admin account again.