Computing Security Basics

The computer virus is now 20 years old. The earlist ones used to spread by floppy disk.

Time for a friendly reminder of some simple things you can do to remain safe on-line in today's threatening environment.

Security Baseline

Job one: You need complete up-to-date security software. Once you are infected, it is extremely difficult to remove the latest threats, which are extremely sophisticated. You can: lose all your data, and / or have your bank account and other assets cleaned out as a result of stolen passwords and other information.

Don't be fooled by a popup window that tells you you might be infected by spyware and tries to frighten you into installing it - when you do, your computer becomes infected with this very nasty, persistent, damaging software. Only use legitimate software that you have heard recommended from a trusted source.

I recommend Zone Alarm.


Be careful what you download - if the file or program is from an unknown source you risk loading malicious software on your computer. Don't respond to e-mails requesting personal information: legitimate companies won't ask for that. And, be smart about your password - the best ones are easy to remember yet long and difficult to guess and include a combination of letters, numbers, even punctuation and special characters.

Code and Data

Learn the difference between passive data and active code, and avoid passing control to the latter. Unfortunately Microsoft makes it rather too easy to do this, but they may be improving future releases of their OS. You can also turn off the default of hiding extensions for known file types (it is in Folder Options).

Here is a handy chart listing common file types that will hopefully help prevent you opening a file that can be dangerous to your system.

Zero day

It takes time to identify new viruses and issue protection. Therefore, I have the policy that any new program be saved first to my hard drive and wait for one week for the anti-virus software to update before installing. And, I recommend being extremely selective about whom you trust and installing only those few bare minimum programs you really can't live without. Even in the absence of deliberately malicious code, every install is a chance for incompatibilities to cripple your system.

I am horrified that some applications' installation programs are still requesting that the user temporarily disable their anti-virus software. Running new programs for the first time is precisely when the virus checker is needed the most.

Not allowing end-users to log in as a local administrator or root will defeat 70 percent to 80 percent of today's most popular threats.

In general, if something comes to you unsolicited, it is highly suspect. You will do much better by seeking things out. This includes programs that promise to improve your computer in all kinds of ways.

It is true that sometimes your computer can get infected without even clicking on anything. This happens when new vulnerabilities are found, and the solution is to keep your system patched with the latest security fixes that apply to your system.


Tests have shown that almost all e-mail addresses on spammers' lists come from web pages. So, ask to be removed from any on-line references, or, in the alternative, there are ways to obscure the code from spammers while still providing the convenience to legitimate users.


Let's dispel a myth: "If it is from someone I recognize, it must be ok": not true. Another common concern is: "Someone received an infected file from me; I must be infected": wrong: viruses can spoof the address they appear to be from.


Finally, remember to make backups of your important data.

Happy computing!

© copyright 2006-2007, O. P. Martin