NCLspring.04


North Carolina Libraries                                                                                                                                               Spring  2003 — 63

 Anti-virus Software

by Ralph Lee Scott

ired to the C

orld

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This column is the third installment of a four-part series on computer security. The recent“Mydoom” virus attack was an example of a
fast-spreading Internet virus that clogs incoming mail
boxes. Many of you have already received a ton of e-
mails from people you have never heard of, or mes-
sages from “PAYROLL,” “Message returned,” or “TRAF-
FIC OFFICE.” These were distributed to you because
someone did not keep his/her computer anti-virus
software up-to-date and/or opened an e-mail attach-
ment that contained the virus. Outside of the admoni-
tion not to open e-mail attachments from people you
don’t know, what can you do to prevent the spread of
viruses to other computers?

The standard method is to purchase, install, and
run anti-virus software such as Symantec/Norton
AntiVirus or McAfee VirusScan. Recently, however, a
new wrinkle has been introduced to this standard
method. Trend Micro is now offering a free online vi-
rus-scan service at housecall.trendmicro.com. McAfee
and Symantec/Norton now offer similar services.
When you go to the housecall.trendmicro.com Web
site you can select the “Scan your PC” link and have
an interactive scan done for free. No updates are neces-
sary and you always have access to the latest version of
scanning data files and software. You do not have to
use up disk space with the anti-virus software and up-
dates. If your computer files are damaged or infected,
you can isolate or remove them, usually without dan-
ger to your operating system. If you are on the road
and do not have access to corporate or networked vi-
rus file updates due to a firewall, you can still scan
your computer if you have an Internet connection.

These free scanning services work in the following
manner. A small program is downloaded to your com-
puter that checks for drives to scan. You are then given
a menu list from which you select those drives you
want to be scanned. At this point, these scanning ser-
vices work like traditional scanning software. Files can
be quarantined or deleted as desired. Symantec/Norton
and McAfee now have similar free services available at

their Web sites.
Computer viruses either plant a small program on

your computer (1) by moving around in e-mail mes-
sages (like the ILOVEYOU e-mails that we all get) that
take control of your e-mail address book, (2) through
worms (a small piece of software that repeatedly infects
other computers – CODE RED is an example), and (3)
through so-called Trojan horses (small programs that
are programmed to erase your hard disk). These viruses
take advantage of human curiosity and are executed
by simply opening the ILOVEYOU message. You
should be wary of e-mail addresses that include the
.com, .vbs., or .exe file extensions. The best policy is to
never run any executable files that you receive.

It is also a good policy not to open e-mails that
are unexpected. Simply delete these suspicious e-mails
from the “Inbox” several times a day, using a filter
system that places e-mails from known senders in in-
dividual boxes (such as USENET group mail, family,
colleagues) and leaving the unknown senders’ e-mails
sitting alone in the “Inbox” where they can be deleted
in bulk.

Some e-mail services, including EarthLink and
MSN, permit you to go to a higher level of spam block-
ing. Unless a particular e-mail has been “certified”
through some means, it is blocked. The checking for
certification is usually done by checking incoming e-
mails against known e-mails previously received or
from addresses in your address book. If you select this
higher level of security, non-valid e-mail senders must
be approved by you before the e-mail is delivered to
your Inbox. An excellent way to get rid of spam, this
service should be included in future e-mail program
releases.

It seems like every few days a new virus attacks
with a slightly different twist. The only way to protect
your computer is to keep your virus data files up-to-
date or use one of the free scan programs offered by
the major anti-virus firms. In the next “Wired to the
World” column we will conclude this series on com-
puter security.

http://housecall.trendmicro.com