I have Eroom running IIS smtp server in order for the app to receive mail. The problems seem to be:
1. Exchange relays to the SMTP server but the TO field in the email can't be resolved by the SMTP server because it will say From: Bob smith rather than Bsmith@maindomain.com 2. Outlook will put single quotes around the SMTP server's domain email address which will return a 5.1.1 error. It will be looking for 'firstname.lastname@example.org'
I found both of these by experimenting with the inetpub/drop folder on the Eserver. If I have just both the straight email addresses the mail will be delivered. Change one and it goes to BadMail. Is there a way for Exchange to relay it to the internal SMTP server with the To and From's just being email addresses?