What is a virus?

Very basically, it is a computer program that installs itself onto your machine and may cause damage to your data, software, machine - or all three. Some virus-type programs mail themselves out to your entire address book without you knowing that they are present on your machine - until you receive resentful email from all your colleagues and friends.

There are a number of different types of viruses. The most popular and virulent ones of late have been in the form of worms or trojans. Without going into too much detail, worms and trojans hide themselves in other data, or attach themselves to it, and so make their way into your machine.

How does your computer get infected?

Your computer may become infected when you download email from someone who's machine has the virus. It may come from a stiffy disk and it could also come from a web site or from software that you download off the internet. Worms often find their way into your machine through vulnerabilities in your software. Windows and Microsoft programs like Outlook Express, Word and Internet Explorer are particularly vulnerable to such exploits.

Anti-virus software

Most anti-viral (av) software provides options for you to configure protection settings. Some av programs can slow your machine down, but if you only switch on the email and internet scanning or protection options, this should not happen. In addition, you should perform a 'system scan' (anti-virus scan of your entire C\: drive) once per week. Often, you can set this to happen at night or when you are not using your machine. This is preferable - don't use the machine while the scan is running. It can take some time, as many modern computer systems have a large number of files to scan.

I recommend the commercial software Macafee or Norton. Try it out in a free trial of 30 days first (NOTE: Macafee will not allow you to download if you are outside the United States - a black mark against them, as far as I am concerned. In addition, they have said that they will not block the FBI's trojan keylogger, code-named 'Magic Lantern' [see references below for more details]. Yuck - another black mark. However, their software is excellent for av scanning). Both Macafee and Norton are available from most software vendors and computer stores.

You may have the software installed and configured, but you can't relax yet. New viruses are released all the time and you need to keep your program updated. Purchasing the software will entitle you to free updates - these usually need to be performed once per week. It is called updating your virus pattern files, or virus definition files. Your av software needs to know the characteristics of the latest viruses so that it can scan your computer for them - and this can only happen by updating. Here at SANGONeT, we usually have one person download the update and then we copy it off her machine using our office network. If you are in a similar situation, you could do this.

Don't forget to run a system scan whenever you have downloaded and installed the new update!

Other ways to avoid virus infection:

* Don't open email with strange-looking attachments
* Use non-Microsoft email programs e.g. Pegasus Mail or Eudora Lite (both free)
* Be careful about using stiffy disks on your machine - always scan them first
* Don't open unlikely looking mail, e.g. a message from the Receiver of Revenue with the subject "I love you" is almost certainly the infamous I love you virus
* Make sure you have macro and heuristic scanning selected on your av program (this will often be under 'advanced' in Norton)
* Don't forget that you can get viruses in Microsoft Word documents too - the dreaded Macro viruses.

Coping with viruses

Ack! Your computer got infected - what can you do?
* Run an av scan immediately
* Close down all programs
* If the av scan doesn't work, use someone else's machine to look up how to remove it on the Symantec virus definition site. You can also type the virus name and the word remove into Google, and you will probably find information on how to take it off your machine
* Don't send any email until you are 100% certain that you have cleaned your computer
* Find the message/document that contained the virus and delete it completely from you computer if your av can't clean it
* If you are uncertain about what to do, call the vendor of the av software and ask for help, or ask someone who is knowledgeable about computers

A large part of looking after your data is common sense, and regular maintenance. Use the tools available and you should stay safe.

References and links to help you:

Viruses, trojans and worms defined, and other interesting and useful information.

Macafee Virus Scan av software.

Norton Anti-Virus av software.

Norton 30 day free trial download site.

Virus and virus hoax lookup.
Type the virus name and press enter on this web page - you will see information about the virus or hoax. This site is worth bookmarking.

Alternative email software
* Download Eudora or Eudora Lite here.
* Download Pegasus Mail here.

Read more about the FBI and Magic Lantern here.