Avoiding Viruses

Posted 17 years ago by Internetrix

3 Minute(s) to read

In a sequel to one of the most damaging virus outbreaks this year, early June saw the arrival of Bugbear C, a new variant of the original Bugbear virus with an even more dangerous payload.

Using the same infection mechanism - a security hole in Microsoft email clients - this virus has infected many thousands of people, including some of our clients. Considering the security hole has been known about for well over 12 months - and Microsoft has had a patch available for free to fix it - it is actually amazing that people still get viruses.

Viruses are just computer programs, and to infect you they need your permission to run, or they need to exploit a security hole in something like your email program. To help protect you, we have compiled a quick list of do's and don't's to protect yourself against viruses online.

1. Don't open attachments with certain file extensions - while the cunning virus writer can deliver a virus payload in many file formats, they mostly come through in files attached to emails with one of the following file extensions. Remember, it is the last three letters of the filename that count - sometimes virus writers try and trick you by putting multiple extensions in, like kornikova.jpg.pif. The golden rule here is: when in doubt, don't, even if you think the person forwarding it to you is trustworthy or knowledgeable.
a) .exe & .com - these are executable files and the most dangerous. They can do almost anything to your computer without your permission.
b) .pif, .scr & .vbs - these files can access built-in functions in Windows to cause you grief. This is how Bugbear sends itself around.
c) .doc - Word documents themselves aren't a problem, but they can contain "macros" which can carry viruses. Make sure you disable macros in Word.

2. Regularly "patch" your machine - this used to be tricky to do, but a couple of years ago Microsoft launched WindowsUpdate.com. This website is amazing, and by visiting it, you find out what patches and upgrades your computer needs. Our advice is to visit this site at least once a month, and if you have never visited it, go there today - everyone who got Bugbear got it because they were not patched.

3. Read Install Dialogue Boxes Carefully on Websites - some programs are actually best installed from websites, an example being Macromedia Flash. Online installs, however can also be a way to infect your machine with a nasty program - the recent 1900 virus was an example of this - so make sure you read any windows asking for your permission to install something carefully and only install software from sources you trust.

4. Regularly scan your machine - if you are running an antivirus program, make sure you regularly scan your machine, and ensure that you have the latest virus definitions - scanning depends on the programs knowing what viruses look like to find them. If you don't have antivirus software, you should regularly visit http://housecall.antivirus.com - this is a free online virus scanner that will scan your computer.

If you follow the four simple steps above, your chances of getting a virus are dramatically reduced. As an additional step, you should probably make sure you have some free firewall software running on your machine - Zone Alarm ( www.zonelabs.com ) can help protect you and others even if you get infected, by stopping the virus in its tracks.

Of course, if you have questions or problems, please don't hesitate to call or email us or contact your hardware supplier.