On a Windows Server 2011 SBS, I have a problem with Exchange. The SMTP is not working. Using a telnet test from the server itself on the lan ip it pops up the following error:
421 4.3.2 Service not available
Connection to host lost.
-it has the same behavior doing the test even from another machine
-the firewall is turned off
but using "localhost" instead of 192.168.x.x is working