Hi - I have had to rebuild my Windows network - had 2 DC's go down...I am trying to connect an existing server to my Domain. The existing server is now a WG server. I believe I have a problem with my DNS settings: from the server that I'm trying to add to a Domain - I can ping the IP address & name of the server (DC) running DNS, however, I can not ping the whole FQDN - server.domain.local When I try pinging the FQDN i get the message "unknow host xxxx.xxxx.xxxx When I try to add this server to the Domain I get "The following error occurred validating the name "xxxxx.xxxxx, this condition may be caused by a DNS lookup problem." "The specified domain either does not exist or cound not be contacted". I have tried to look up the message but have not been able to fix the problem. Please help Thanks heaps Mark

so you lost 2 domain controllers at once? wow. are there any left? what is currently hosting dns for the domain? is your workgroup server pointed to whatever dns server is left?

try using dcdiag /fix and netdiag/fix in network configuration set a manual dns entry to the domain u try to join to.