• Working with Email Safely
and Securely
• Keeping Intruders Out of
Your System
• Surfing the Web Securely
• Blocking Pop-Up Windows
• Understanding Internet
Explorer’s Advanced Security
• Security and Privacy Options
for Windows Media Player
Implementing Windows
XP’s Internet Security
and Privacy Features
As more people, businesses, and organizations establish a
presence online, the world becomes an increasingly
connected place. And the more connected the world
becomes, the more opportunities arise for communicating
with others, doing research, sharing information, and
collaborating on projects. The flip side to this new connect-
edness is the increased risk of connecting with a remote
user whose intentions are less than honorable. It could be a
packet sniffer who steals your password or credit card
number, a cracker who breaks into your Internet account, a
virus programmer who sends a Trojan horse virus attached
to an email, or a website operator who uses web browser
security holes to run malicious code on your machine.
Admittedly, online security threats are relatively rare and
are no reason to swear off the online world. However, these
threats do exist and people fall victim to them every day.
Luckily, protecting yourself from these and other e-
menaces doesn’t take much effort or time, as you’ll see in
this chapter, in which I discuss the Internet security and
privacy tools built into Windows XP.
Working with Email Safely and
Email is by far the most popular online activity, but it can
also be the most frustrating in terms of security and
privacy. Email viruses are legion; spam gets worse every
day; and messages that should be secret are really about as
secure as if they were written on the back of a postcard.
Fortunately, it doesn’t take much to remedy these and other email problems, as you’ll see
over the next few sections.
Protecting Yourself Against Email Viruses
Until just a few years ago, the primary method that computer viruses used to propagate
themselves was the floppy disk. A user with an infected machine would copy some files to
a floppy, and the virus would surreptitiously add itself to the disk. When the recipient
inserted the disk, the virus copy would come to life and infect yet another computer.
When the Internet became a big deal, viruses adapted and began propagating either via
malicious websites or via infected program files downloaded to users’ machines.
Over the past couple of years, however, by far the most productive method for viruses to
replicate has been the humble email message. Melissa; I Love You; BadTrans; Sircam; Klez.
The list of email viruses and Trojan horses is a long one but they all operate more or less
the same way: They arrive as a message attachment, usually from someone you know.
When you open the attachment, the virus infects your computer and then, without your
knowledge, uses your email client and your address book to ship out messages with more
copies of itself attached. The nastier versions will also mess with your computer by delet-
ing data or corrupting files.
You can avoid getting infected by one of these viruses by implementing a few common
sense procedures:
Never open an attachment that comes from someone you don’t know.
Even if you know the sender, if the attachment isn’t something you’re expecting,
assume that the sender’s system is infected. Write back and confirm that the sender
emailed the message.
Some viruses come packaged as scripts that are hidden within messages that use the
Rich Text (HTML) format. This means that the virus can run just by viewing the
message! If a message looks suspicious, don’t open it, just delete it. (Note that you’ll
need to turn off the Outlook Express preview pane before deleting the message.
Otherwise, when you highlight the message, it will appear in the preview pane and
set off the virus. Select View, Layout, deactivate the Show Preview Pane check box,
and click OK.)
Install a top-of-the-line antivirus program, particularly one that checks incoming
email. Also, be sure to keep your antivirus program’s virus list up to date. As you
read this, there are probably dozens, maybe even hundreds, of morally challenged
scumnerds designing even nastier viruses. Regular updates will help you keep up.
In addition to these general procedures, Outlook Express also comes with its own set of
virus protection features. Here’s how to use them:
1. In Outlook Express, select Tools, Options.
2. Display the Security tab.
CHAPTER 21 Implementing Windows XP’s Internet Security and Privacy Features552

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