I have an Exchange 2007 SP1 installation, on a Windows 2008 server.
On the same server, I run an IIS webserver, with the CMS e107.
As e107 has options to send email, i.e. when new users are created, forgotten password etc., I have set up the mail options in the e107 to use SMTP.
Settings are for this, is to use the localservers port 25.
On Exchange I have created an Open-relay connector, with Remote Network Settings to only include its own IP address (since this is the address, that the webserver is running on as well).
To actually let it become an open-relay for non-authenticated servers/systems, I followed this guide from MS: http://technet.microsoft.com/en-us/library/bb232021.aspx
Neither of the solutions seems to work however.
I then expanded the Remote Network Settings to include the entire local network, still with no luck.
I also restartet the Transport service in between all settings I applied.
By now, I'm pretty lost in what to do, as can't seem to find information on this particular problem anywhere - and according to various sites/forums, this is the way to make exchange accept third-party systems.
Also, there are no firewall running on the server (which shouldn't matter anyway, when it's all local traffic).
Hope someone has a genious suggestion here :-)