Lost my Backup DC 2003 server so I Extended SBS2003 AD forest and domain to support 2008 server. ran ntdsutil to remove the missing server from the domain. After adding a windows 2008 server to AD and as a BDC with DNS services, I am unable to add any windows xp or server 2003/2008 computer to the domain. In conjunction with this on the SBS PDC I have been received kgbt machine and user 675 and 680 pre-authentication errors (I assume they are related to machines/users trying to authenticate against the domain) which is probably why I can't add the new machines to the domain. OF note, the new machines can see the PDC and BDC with the PDC listed first. I have also tried changing the order and listing only the PDC and/or only the BDC.