New SBS2003. Client existing email is hosted, so currently BOB@company.com uses Outlook with POP3 to log into the remote server to send & receive email. I installed a POP3 connector and used the credentials for BOB and can download emails fine. I add another address in the connector for JOE and both are working. Emails are going into the correct mailbox. There is a one to one relationship with the pop account and the mailbox. (Not a "catch-all" account).
Sending is another matter. The outgoing SMTP connector needs authentication. OK, I set up BOB in the smarthost, but JOE can't send email because he can't send as BOB. Get it? I added another SMTP connector with JOE's credentials, now JOE works, but BOB doesn't (error says BOB can't send as JOE). I changed the SMTP Connectors to deny all users by default and allow only BOB or JOE depending on which connector... nope, still not working.
The idea is that the hosted email will remain safe in the event of a catastrophic failure of the Exchange server. After all, these hosts have redundant servers, redundant internet connections, and it's cheap... why not use it? The client just wants to be able to use group calendars and get all their email in one place - Outlook using Exchange. Then in the event of a failure, he can still get individual emails by going to an Internet cafe and logging into his host's webmail service.
I thought maybe I could send directly using SMTP from the server, but email wasn't going through. I later realized that reverse DNS lookups made me look like a spammer. I tried adding an MX record for this server (using dynamic IP services). When I look up MX records now, it shows up, but messages are still stuck in the queues. I can clear the queues, but new messages still go into the queues and never leave. Is it because of the dynamic DNS service? Reverse DNS still doesn't match, so I'm being rejected as a spammer? With one SMTP connector and one POP3 account everything works as I'd expect, but I need 12 email accounts.
Please HELP!!! How can I make this work and satisfy this new client?