I have my Exchange 2003 bridgehead server talking to a Barracuda Spam Firewall 300 appliance for it's smart host. It hums along for a while and then all of a sudden gets a 'The connection was dropped by the remote host.' error and goes into retry mode. It retries the three times one minute appart, then waits 10 minutes for the fourth try which usually reconnects and flushes the queue. Barracuda claims there is nothing wrong on their end. Any ideas? Is there a log I can check to get more info as to what is going on with the Exchange server?
If I force a connection manually it seems to connect, change to active and flush the queue.