We have our exchange 2007 server setup to receive emails from our salesmen that are on the road. They are connecting via whatever network they are on and thus have a variety of ips. We allow them to connect and send smtp via ssl and authenticated smtp. All of this works fine.However, we are getting spf failures and lots of spam kickbacks because one of the 'received from' lines is their original sending address (which is entirely random). How do I make exchange not stamp the original received from ip into the message header?btw, this same thing on other mail servers like abilitymail is easily taken care of by checking their HIDE IP option. I need to find the equivalent setting on exchange.thanks

I'm still thinking about your question and trying to determine if this is intended SPF behavior, but in the mean time here is a possible answer:http://www.expta.com/2008/06/using-exchange-2007-header-firewall.html Mike Crowley A+, Network+, Security+, MCT, MCSE, MCTS, MCITP: Enterprise Administrator / Messaging Administrator

You can accomplish this by removing Ms-Exch-Send-Headers-Routing permissionfor anonymous usersfrom the SMTP sendconnector used to internet. Remove-ADPermission <name of SMTP connector to Internet> -User "NT Authority\Anonymous Logon" -ExtendedRights Ms-Exch-Send-Headers-Routing more help about SMTP connectors permission model http://technet.microsoft.com/en-us/library/aa997170.aspxlasse at humandata dot se, http://anewmessagehasarrived.blogspot.com

More resources: How to hide internal server info in outgoing message header (Similar Case) Removing internal host names and IP addresses from message headers