Never mind possession...
prevention is nine-tenths of the law when it comes to avoiding spyware (unless
you're already infected). The following steps will assure that your PC is
as well protected as it can be against the horde of malware that lurks on the
Internet.
Step 1: Keep Windows updated
As I've
said before, this is the absolutely essential first step to any form
of secure PC. You must keep Windows updated with new fixes and patches
as they are released, or else any other security measures you
take can be undermined by vulnerabilities within the operating system
itself.
Use Windows Update,
and if you are using XP,
use the automatic updates too. The same goes for firewalls, anti-spyware
and anti-virus software. Always update each time you use them
also.
Step 2: Use a firewall
Firewalls can prevent problems with spyware
and computer viruses by effectively closing off the ports of entry into your system from
the Internet. In fact, that's exactly what they do; close the ports which allow your
system to form connections with remote systems. A traditional firewall allows anything
to leave your computer, but allows nothing in unless it has been
requested.
For example, when you view a
web site, your system first sends a request to the server that hosts that site,
asking for the data needed to display the page. Any unsolicited data
from outside the computer will be dropped, unless it has been specifically
allowed.
Of course, a firewall will not
prevent viruses or spyware coming into your system with requested data (such as
an email-born virus, or a browser-hijacker that installs itself from a
website). Despite this, firewalls are still an essential part of a secure
system, since they prevent malicious users and software from intruding into your
computer without your knowledge or consent. Most firewalls also conceal
your computer by refusing the 'PING' requests used to locate computers over the
Internet.
There are several types of
firewalls available, including some excellent free choices. Windows XP
comes with a built-in firewall, which is simple and effective. Any Home
Internet sharing device (router) will come equipped with a firewall which will
protect every PC hooked up to it.
When it comes to spyware
defence, the best choice is a software firewall like Zonealarm or the Sygate personal Firewall (UPDATE: no longer available). The advantage of these products is that they also monitor and
control data leaving your system. Since most forms of spyware and Trojan
horse virus software do their damage by transmitting data out of your system,
they can be found and contained by this type of firewall.
For more information on
installing and configuring firewalls, see our guide here. For
more background information on firewalls and Internet security, see this PCstats article.
Step 3: Use Anti-virus software
Another
essential security step. Most anti-virus packages now protect against many forms
of spyware and malware as well as traditional viruses. Use a major package like
Symantec's or MaCafee's offerings and make sure you keep it updated. Most
products will update themselves and scan your system automatically at intervals,
but they cannot update if you are not connected to the Internet. See our article here
for more details.