>After receiving some emails my exchange server attempts to make a connection
>to the sending email server on port 137. I have my firewall configured to
>block all outbound traffic except on four or five ports. Is there any
>benefit to me for my server responding to the email with the connection?
None. Don't allow port 137 into, or out of, your network.
Quote:>Should I be allowing outbound port 137 connections?
Exchange, being a Windows application, feels compelled to use NetBIOS.
If the other end of the connection is another Exchange server on your
own network this might be okay, but not to another Exchange server on
sombody else's netork!
MCSE+I, Exchange MVP
MS Exchange FAQ at http://www.swinc.com/resource/exch_faq.htm