Greetings,

I have several clients on my Windows Server that is running Server 2008 and IIS 7.  I setup "Localhost" in the SMTP server settings, and it has been running with no problems until recently.  I installed some security patches, and I am seeing the following error:  Mailbox unavailable. The server response was: 5.7.1 Unable to relay

Thininking that is was the security patches, I went ahead and uninstalled them.  Still seeing the same error message.

I am not very savy with Severs and IIS settings, so I asked my server administrator to have a look at the server to make sure the was nothing changed.  We looked at the "Hosts" file to ensure the "localhost" setting was defined, and we also checked looked at the IIS settings.  Everything looked correct as though nothing had changed.

Do any of you have any ideas as to how we can get this resolved?

Thanks in advance for your time and knoweledge.

Kind regards,
-Shane

Thanks for the quick response.

I've done some research, and although what you are saying makes sense - I am not exactly sure how to accomplish what would seem a simple task.

The only thing I can find is procedure literature about IIS 5, and how Windows Server 2008 is not a mail server and that SMTP needs to be installed.  In  looking at the server configuration, SMTP is installed.  When I go into IIS, the only SMTP settings that I see is found within the domains themselves.

Am I missing something in IIS 7 that gives me the ability of changing the relay option?

Thanks again,
-Shane