The setup of the Exchange Server on a system running behind the WinProxy computer is a four-step procedure. (NOTE: Step 2 is optional. In other words, you only do step 2 if you want to allow external users access to your internal Exchange Server.)

---

1. In WinProxy, click on File -> Settings -> Protocols. Make sure that the box next to 'Mail' is checked.
2. Click on 'Mail Setup'.
3. Change the ports for both SMTP (25) and POP3 (110), so that they do not conflict with the Exchange Server, which also uses ports 25 and 100. In our example below we changed the SMTP port to 8025 and POP3 to 8110.
4. Check the box next to 'Incoming Proxy for SMTP'.
5. For 'Internal Server IP' enter in the IP address of the internal Exchange Server.
6. For 'Internal Server Port' enter in 25 (by default).
7. Click on OK -> OK.

To allow users on the Internet to connect to your internal Exchange Server you will need to map port 110 (incoming, TCP) to allow the mail to pass through the firewall.

In WinProxy,

1. Click on File -> Advanced Settings -> Mapped Ports -> New.
2. For 'Mapped Port Name' enter in any name you would like.
3. For 'Proxy Port' enter in 110.
4. For 'Destination' enter in the IP address of the internal Exchange Server.
5. For 'Destination Port' enter in 110.
6. Under 'Mapped Port Type' select TCP.
7. Under 'Mapped Port Direction' select Incoming.
8. Click on OK -> OK.

By creating this mapped port for 110, you have opened up the standard port on the proxy server that email programs use to connect to their POP3 server. Hence, allowing external users the ability to request for their email from your Exchange Server.

NOTE If you are using IMAP instead of POP3, then all you will need to do is enter in port 143 under 'Proxy Port' and 'Destination Port'.

1. Upon installing the Exchange Server, you will need to install its 'Internet Mail Service'. To install this service open up Microsoft Exchange Administration. Click on File -> New Other -> Internet Mail Service. An 'Internet Mail Wizard' box will pop up. This wizard will walk you through installing the Internet Mail Service.

2. Once the Internet Mail Service has been installed, double-click on it.

3. Click on the 'Connections' tab. For:
   • Transfer Mode: Select 'Inbound & Outbound'.
   • Message Delivery: Select 'For all messages to host'. In the box directly below this, enter in the internal IP address of the WinProxy computer.
   • Accept Connections: Select 'From any host (secure or non-secure)'.

4. Click on the 'Routing' tab.
   1. Select 'Reroute incoming SMTP mail (required for POP3/IMAP4 support)'.
   2. Click on 'Add'.
      • Email sent to this domain: Enter in your registered domain name.
      • Select 'Should be accepted as inbound'.
   3. Click 'OK'.

5. Click on Apply -> OK, then stop and start the 'Internet Mail Service'

NOTE Make sure you stop and restart the 'Internet Mail Service' every time you make a change within it. Since WinProxy 3.0 allows you to perform DNS lookups through the firewall you can choose to either select under 'Message Delivery' "Use domain name system (DNS)" or "Forward all messages to host".

1. Outgoing Mail Server - Enter in the IP address of the internal Exchange Server.
2. SMTP port - Enter in 25.
3. Incoming Mail Server - Enter in the IP address of the internal Exchange Server.
4. POP3 port - Enter in port 110