Domains and Small Business server

We have windows small business server running. I have just put in a new server and had the old and new server running both small business server running on the same network. I have removed the old server from the network and after 7 days the new server shuts down due to the SBcore error 1011. Two domian controller have been detected on the network. I have even demoted the old server, but i still get the same error on the new server.Is there any way of solving this with out re-istalling the new server.