How is SMTP relay configured on Exchange 2007 to allow non-outlook clients to send email? The following post has been followed -
Once configured according to these instructions, email is still unable to be sent with a non-outlook client.
The objective is to allow internal hosts on the 192.168.0.0 subnet that are not members of the domain or have Outlook to send email using the internal hostname or IP address (of the Exchange server) as an SMTP server. Non-Authentication to the Exchange server by these internal hosts is the preferred method however, authentication can be supported if necessary (from a function or security stand-point).