We currently have this setup:
Exchange 2007 in our main office.
Remote users connecting to Exchange 2007 with Outlook via a VPN
Remote location is part of main office domain.
Remote location has it's own DNS/AD/DHCP server.
We are going to be adding the remote office to it's own domain, since it is technically a different company. However, we want to host their email on our exchange 2007 server.
We do not want to use OWA / web based email. Rather, we want them to open Outlook like they do now, but we want it to access the server over the net on our public IP since we will be removing the VPN connection.
Is this possible to do? If so, which ports need to be opened and is there anything else we need to configure in Exchange? (e.g. allow theirdomain.com to log in?)