Hi there I've just received an email from an address that has our own company domain attached to it that is a spoof. How can i setup my Exchange Server so that it does not accept externalemails fromthat originate from my internal domain? Any help is much appreciated. C

One option would be to use SPF records. See here for more info: http://microsoft.com/senderid The challenge however is when you block legitimate messages. for example if you have a pop3 user sending mail to an external recipient, but relaying through your exchange server, how do you allow him to send from your domain but block others? If you have no senders outside your Exchange Org this isnt an issue, but be sure to think it through before you block anything.