I just recently migrated my domain from server 2003sbs to server 2008r2. Everything was running great until recently, I started getting the 13508 FRS replication error in the event viewer. DCdiag list the following errors 1256 (remote system unavailable), 8524 (DNS look up faild), and a 1722 (RPC server not availabe). The first two are obvious since the box has been removed form the network, DNS, and DHCP scope. However, I do not recall demoting the 2003sbs and one day found it removed from service. I am wondering if the 1722 error is due to not demoting the 2003sbs server? Can the 2003sbs be demoted via dcpromo?