In the interest of personal computer security, I have added this page to inform my site visitors about some extra measures needed to avoid some of the commercial spyware and ad-tracking cookies most of us receive while surfing the net. This is in addition to viruses and trojans which we may receive during opening infected e-mail attachments or installing malware-ridden applications.
First of all, to avoid viruses, never open an e-mail attachment other than a document or picture-type file. These are generally ok from people you know, but strictly avoid those such as .exe , .zip , .vbe and so on, even if sent from a friend, as they could have had their e-mail programs compromised by malware applications which may have sent the emails to you without their knowledge.
Watch for double extensions, like .jpg.exe and so forth. The file should immediately open in its proper viewer rather than try to install anything. The newer versions of Windows are a lot more secure, and will alert you if something it trying to install itself, so you can interrupt it there and stay safe. Try to be sure that any new software you install on your system is reputable and virus-free. Some sites like CNET offer apps which are certified "safe and spyware free".
In addition to viruses, you can receive "back-door trojans" which make your computer vulnerable to being used for denial-of-service attacks on other websites and government agencies without your knowledge, and your web address can be traced back to you. When infected with such a virus, certain "crackers" continuously scan web addresses (such as yours) for open ports, and if you have such a trojan, they can recruit your computer remotely.
It's worth the time to keep an eye on your firewall and which software you allow to access the web.
The following is a list of sites which have free software and tests for Windows, which I assume most of you are using at this point. Write me if you have any questions or need info for other operating systems. Linux and Apple operating systems are a lot more secure than Windows, and in most cases virus-proof, unless you get tricked into installing some malware yourself.

New for 2010: Much of this page has been rewritten, as much of this information dated back to around 2004 or so.
Suggestions: Rather than Internet Explorer, use a more secure browser such as Firefox, Google Chrome, or Opera.
If you dislike cookies, use one browser for your banking and sites that need cookies enabled, but another for casual surfing, then you can delete the cookies on that browser as often as you like.
Rather than McAfee and payware virus/spyware protection apps, there are a number of free apps which perform quite well, and include features like scanning your email, checking websites you visit for exploits, and removing spyware.
A recent (Fall, 2010) study rates the free vesions of these antivirus suites highly:
AVAST     - - recommended
AVIRA
I've also used AVG Free quite a bit in the past:
FREE AVG
Here's a free antispyware app I've just been trying recently (you have to start the scan manually):
SUPER ANTISPYWARE
And another I've used an can recommend (not sure if they will always have a free version):
PC TOOLS SPYWARE DOCTOR WITH ANTIVIRUS
Here are a few old "standby" sites I frequented in the past, which offer free apps and tests :

Gibson Research        Scroll down to find the "Shields Up" link and this site will test your shields & probe your ports for vulnerabilites. This site also has many articles & links of interest.

Ad-Aware        Free ad spyware removal and disk/registry scan program, works very well in deleting the ad trojan programs, and once you are confident that you have taken steps to reduce the incidences of these, you need only run it occasionally. One note though, I have found that downloading some programs from reputable companies will also install spyware, so try to use reputable software, and decline the extra features you do not need.

More tools:
Spychecker.com

...and a good free registry cleaner (beware all the "trialware" ads on websites to scan your computer, just use this):
Eusing Free Registry Cleaner

Good luck with all of this, and happy surfing...


I hope this has been helpful, and thanks for stopping by. Please send feedback or other info you would like to see added here...