Expert: Brian Benosky - 4/3/2008

Question
My work computer was recently infected with 3 Trojans. My manager never installed a virus protection program onto the computer. What is the absolute best free anti-virus, and Spyware protection out there? What is the difference between spyware and a virus?

Answer
Hi Anna

To answer your second question first, a virus is a malicious software program that can cause harm to your computer.  
This can be in the form of corrupting or damaging files such as your personal
documents, pictures, or music and can make your computer unusable.  It is easily
spread to other computers through email or sharing media such as floppy disks
or USB drives.  Some viruses can duplicate themselves and travel through networks.  
The most common way to get a virus is opening an infected email attachment.  

Spyware is a malicious software program that steals information from you by
spying on your activity on your computer without your consent.  The most common
way to get spyware on your computer is through surfing on the Internet or when
you access websites that have peer-to-peer file sharing such as free music and
video downloads.   While these products are “free”, you still pay for them by
allowing an invasion of your privacy instead of paying with your money.  When
spyware gets into your computer, it usually tries to steal information about your
internet browsing habits, email messages and addresses, user names and passwords
and credit card information.  If the spyware is not removed, it can transmit this data
to another person’s (the host) computer over the internet.  It will then be used to
either send you popup ads, steal money from you, send you spam and scams, or sell
your personal information to other scammers.

As for the best free protection, go to the link below to view some anti-virus program suggestions:
http://forum.hijackthis.de/showthread.php?t=8897
Personally, I use Avast Home for anti-virus:
http://www.avast.com/eng/avast_4_home.html
And for anti-spyware, I use Spybot Search and Destroy in combination with AdAware:
http://www.safer-networking.org/en/index.html
http://www.lavasoftusa.com/products/ad_aware_free.php

I hope this helps.  If you need any further assistance, please let me know.

Brian