How to configure Exchange 2003
for use with SpamCat

Related Articles:
How to configure Exchange 2007/2010 for use with SpamCat

Introduction:
In order for SpamCat to function at it's most accurate level, it is necessary for you to configure your mail server(s) to send all of their outgoing messages through SpamCat. SpamCat uses a suite of heuristic and artificial intelligence engines to filter your organization's incoming email messages, and SpamCat learns from the outbound messages sent by your users so it can accurately score new inbound messages when they arrive.

To prevent abuse by unauthorized users, SpamCat requires SMTP Authentication for all outbound messages relayed through it. Therefore, you must configure your Exchange Server to perform SMTP Authentication on the outbound messages it relays to SpamCat from your organization.

Step 1:
Using Exchange System Manager navigate to the 'Servers' container. Now drop down the 'Protocols' container. Next find the 'SMTP' protocol and select 'Default SMTP Virtual Server'. Right click on the Default SMTP Virtual Server and choose 'Properties'.

NOTE: Your Virtual SMTP Server may have a different name than "Default SMTP Virtual Server".
NOTE: Your Exchange Server may be configured with more than one SMTP Virtual Server, in which case you should repeat this process for each virtual server.
NOTE: There may be multiple Exchange Servers in your organization, in which case you should repeat this process for each physical Exchange Server.

Step 2:
Select the 'Delivery' tab at the top of the Properties window, then click on the 'Outbound Security...' button. This is where you will enter the SMTP Relay Username and Password that SpamCat has provided for you. Choose 'Basic authentication'. Exchange 2003 uses the term Basic Authentication, whereas it really is SMTP AUTH to the rest of the internet community. The Username is not case sensitive, but it will always appear in an email-style format of "YOURDOMAIN.TLD@client.spamcat.net". The password IS case sensitive, so be certain to enter it exactly as it was provided to you.

NOTE: The SpamCat SMTP Relay Username does NOT correspond to a real email mailbox. Therefore, ALL messages sent to that "address" will always be rejected by the SpamCat servers. Do NOT attempt to use the username alias as a "postmaster" account alias. The SMTP Relay Username is exclusively for performing authentication by your server(s) to send outbound messages through the SpamCat system.

Step 3:
While still on the Delivery tab of the Properties window, click on the'Outbound connections...' button. The 'TCP Port' setting will show you what outgoing SMTP port number your server is configured to use for sending messages. Some ISPs will block their users from connecting to Port 25 on servers outside of the ISPs private network. If your ISP is blocking port 25 and you need to get around it, you can enter port 9025. Port 9025 is SpamCat's alternate SMTP port, it functions exactly the same as Port 25 (the default), and it should not be blocked by your ISP.

NOTE: We recommend that you leave your TCP Port set to the default setting of 25 unless you are certain that Port 25 is being blocked by your ISP. Do not change any other settings on this dialog window unless you know what they are for.

Step 4:
While still on the Delivery tab of the Properties window, click on the 'Advanced' button. Set the 'Smart Host' setting to read: 'smtp-out.spamcat.net'. All outgoing email originating from Exchange on this Virtual SMTP Server will now be delivered to SpamCat for delivery to the internet. Click OK when completed.

Step 5:
After you've completed the above steps you will need to restart your SMTP service for all changes to take effect. Any mail that is currently in the queue might not take these new settings so you might need to send a new piece of mail to test it. After sending a test email you will want to check the outbound queue on Exchange to make sure that the mail did not get stuck in your outbound queue because of authentication errors. Navigate to the Server queue and click on any line that has pending messages and you will see any error status messages displayed at the bottom. If you can see that a message failed because of SMTP AUTH on the remote server, you should double-check the Username and Password that you've configured and try again.

Step 6:
Most modern spam filters use a filtering method known as the Sender Policy Framework (SPF) to determine that email messages are sent from authorized mail servers. Now that all email messages for your organization will be delivered from the SpamCat servers, you should add the following record to all Public DNS zones that are protected under your SpamCat account:
@   TXT    "v=spf1 a mx include:spamcat.net ~all"

Conclusion:
Your Exchange Server should now be properly configured to use SpamCat for all of it's outbound messages. If you have any questions or need more help setting this up please feel free to contact our support department.