Installed Exchange 2010 server running on Server 2008r2. I have a connector running from it to my old Exchange 2003 server. I have only migrated several test mailboxes and I am seeing these errors in the App log. 2102 - All Domain Controller Servers in user are not responding. and 2114 "Topology discovery failed, error 0x80040a02. Look up lightweight Directory Access protocol error code specified in the event description. Are these something to be concerned about. How do I fix or find the cause of the issues?