HiCurrently our exchange server is set up to allow SMTP requests from another local machine that is using ASPEmail to create these requests. The destination email address has no restrictions on it. I have made a copy of the website and it is running on an external machine. I have set up the ASPEmail on this new machine to use my exchange server to send emails. It works fine if the email domain is the same as the exchange server but any other domains get the error 'unable to relay for...'I have added the IP address of this new external machine to the relay restrictions on the exchange server. Is there anything that may be blocking external domains being emailed if the request comes from an external machine?Many thanksAlex

Hi Alex, I suggest you refer to following article: Allowing application servers to relay off Exchange Server 2007 http://msexchangeteam.com/archive/2006/12/28/432013.aspx Please understand that by default, only the authenticated users are allowed to relay message. Mike