Troubleshooting Lab

In this lab, you identify a source of junk e-mail and block it at the Exchange Server 2003 server level. You then discover that the source has been spoofed but that this problem has now been solved. As a result, you no longer want to block e-mails from that source.

To complete this lab, you need to have your test network configured as described in the "Before You Begin" section of this chapter. In particular, you will be blocking and then permitting e-mail from a specific user in the tailspintoys.com domain. If your domain has a different name, substitute your domain name in the exercises.

Exercise 1: Sending a Junk E-Mail

This could be considered a trivial exercise, but if you refine the technique, you will never starve. To send junk e-mail, perform the following steps:

1. On Server02, log in as Don Hall. Open Internet Explorer and access OWA (http://server02/exchange).

2. Send an e-mail message to [e-mail]. The text in this message is entirely your choice, but it could be on the lines of "I want to play guitar like Will Willis. Please send me lots of money for lessons."

3. On Server01, log on as administrator and open your Inbox. Read and delete the offending message.

Exercise 2: Block Junk E-Mail from Specified Domains

Outlook is set with a junk-mail filter that prevents e-mail from sources on your RBL being read by clients. However, when e-mail is coming from junk-mail domains, you want to block it before it enters your organization. You should therefore filter it out at the default SMTP virtual server on your front-end Exchange server.

To block Internet e-mail from specified domains and users, perform the following steps:

1. Open Exchange System Manager.

2. Browse to Administrative Groups\First Administrative Group\Servers\Server02\ Protocols\SMTP, right-click Default SMTP Server, and then click Properties.

3. On the Access tab, under Connection Control, click Connection.

4. In the Connection dialog box, ensure that All Except The List Below is selected, and then click Add.

5. In the Computer dialog box, select Domain.

6. Read the warning in the SMTP Configuration box, and then click OK.

7. Type nwtraders.com in the Name box, and click OK.

8. Click Add in the Connection dialog box, and then select Domain in the Computer dialog box.

9. Type treyresearch.com in the Name box, and click OK.

10. The Connection dialog box should look similar to Figure 11-14.

    
    Figure 11-14: Blocking junk-mail domains

11. Click Add in the Connection dialog box, and then select User in the Computer dialog box.

12. Type [e-mail] in the Name box, and click OK.

13. Click OK.

14. Click OK again to close the Default SMTP Virtual Server Properties box.

15. Send an e-mail from Don Hall to [e-mail]. Check that the e-mail is blocked.

Real World: Have You Blocked Junk E-Mail?

In the real world, it is difficult to test that you have blocked a junk e-mail sender, unless you have software that will spoof that sender. Whether you want to obtain such software, and encourage its supplier, is debatable. In practice, scan e-mail carefully and ensure that nothing more is received from the sender in question.

Exercise 3: Remove an Entry from the Block List

You now want to receive e-mail from Don Hall. To remove him from the block list, perform the following procedure:

1. Open Exchange System Manager.

2. Browse to Administrative Groups\First Administrative Group\Servers\Server02\ Protocols\SMTP, right-click Default SMTP Server, and then click Properties.

3. On the Access tab, under Connection Control, click Connection.

4. In the Connection dialog box, ensure that All Except The List Below is selected, click [e-mail], and then click Remove.

5. Click OK.

6. Click OK again to close the Default SMTP Virtual Server Properties box.

7. Send an e-mail from Don Hall to [e-mail]. Check that the e-mail is received.