Migration Exchange 2003 to Exchange 2010: 421 4.4.2 Connection dropped due to SocketError
Exchange 2010 cannot send mails to Exchange 2003 if it is not authorized to do so. In this case, the queue of the routing group is full with the following error: 451 4.4.0 Primary target IP address responded with: "421 4.4.2 Connection dropped due to SocketError." The problem can be solved by changing the IP address of the Exchange 2010 server on the ... Read more