Have a 10-15 user network that has not configured Exchange, but wants to set up internal messaging now, no external e-mail, no ISP yet (but may want the option in the future). Have set up Win 2K3 Standard networks using IIS and POP3 service, so that the server acts as a forwarder within the internal network. Would like links to doc or advice about setting up Exchange after the fact, or if the POP3 service is a viable substitute. Coming in a little blind on this project, so any hints would be gratefully appreciated.