A system we have sends routine emails out to the company that makes it with support information. That email is sent via our Exchange 2010 server. When I generate this email and send it to my local email account it works fine. When I do the same and send it to any external account it fails with 550 errors related to relaying.
Also, when I try to send an email to any outside address via telnet i get the same thing...See below. Any idea what changes I need to make?
220 cas1.domain.local Microsoft ESMTP MAIL Service ready at Wed, 28 Mar 2012 08:05:28 -0400
250 cas1.domain.local Hello [10.170.1.183]
250 2.1.0 Sender OK
550 5.7.1 Unable to relay
I should note, other than this we are having NO issues in Exchange at all.