How to configure Exchange 5.5 Server

We do not have a comprehensive guide with screenshots for the Exchange 5.5 configuration like we do for the newer Exchange versions. But since Exchange 5.5 seems still (as of June 2006) being quite popular judged by the amount of inquiries we decided to put together this minimal guide:

1. Install the internet mail service (IMS) from the Exchange 5.5 CD (it might not be installed)
2. Add the IMS in the Exchange Server Administrator under "Connections"
3. Configure the IMS:
4. 1. Routing tab: Reroute incoming SMTP email - add "yourdomain.com" to be routed to "<inbound>"
   2. Connections tab: Select "inbound and outbound".
      Configure how you want Exchange to send out email (either by DNS or (better because of antispam measures at the receiving end) via the SMTP relay server of your ISP
   3. Address-Space tab: Add an SMTP Address space of "*".
      Accept from EVERY HOST UNAUTHENTICATED or specify that only the host on which POPcon is running is allowed to use unauthenticated SMTP. POPcon does not do SMTP authentication.
   4. Delivery restrictions tab: Accept email from all sources and restrict mail from nobody.
   5. Internet Mail tab: Configure a postmaster/administrator