Hello,

1. How would I set up sendmail client to use my Exchange 2003 server to route e-mail? One problem I'm having is sending to a distribution list on the domain where there is a user account that is not on the windows domain. I get bounced with a "5.5.0 smtp;550 Sender verify failed" error for the user not on the windows domain. The windows domain user delivers fine (probably since the mailbox is local).

Example:
Distribution List (something@localdomain.local)
user1@localdomain.local (user on windows domain)
user2@outsidedomain.com (user outside local domain)

Here is another problem. When I send to user2@outsidedomain.com alone, it routes but it doesn't relay through Exchange Server.

2. There is no open relay on the Exchange server so any user would have to have relay permissions from a domain user account. How would I tell sendmail to use that account in its settings?

3. How can I get root@localhost.localdomain look like a regular e-mail address like name@domain.net?

I followed the steps in this link to no avail:
http://www.dnsexit.com/support/mailrelay/sendmail.html

I also tried setting up a /etc/mail/aliases file (and running "newaliases") to no avail.

Thank you for any assistance.

You're not getting this error because the list includes a non-local user, you're getting it because the sender address and/or domain is invalid.

I'm assuming the server running sendmail have a static IP address? Perhaps it's even on the same internal network as the Exchange server? In that case, you don't have to mess with authentication settings in sendmail, just add the IP address to the "Relay" list in Exchange System Manager. It's a button on the "Access" tab in the properties dialog of the SMTP virtual server; you'll find it under Servers > "server name" > Protocols > SMTP.

I believe this may be what you're looking for.