> 5.5 installed. Is there any way where the users in the other > network be > given email access without installing Exchange 5.5 in their Yes, of course. You have two good options: 1) Establish a trust relationship between the two domains and create mailboxes on your Exchange server for the members of the other domain. 2) Create a username/password for each outside user in your domain and make sure the passwords are kept the same on both domains (you'll be using passthrough authentication). If you do not have a VPN then it will take some effort to allow the other group access to your server via Outlook (firewall/lmhosts/wins configuration can become complex). Access through a POP/IMAP client wouldn't be too difficult. The combination of a VPN and a trust relationship would be the simplest/best approach.