Computer Virus Guide

This guide explains how you can easily avoid being infected by a virus. Print it out and keep it by your computer for reference.

Your computer can become infected with a virus in two ways -

1. By installing software programs from virus-infected floppy disks or CDs or by downloading and installing virus-infected software from the Internet. In general, this can be easily avoided by only using software from reputable sources.
    
2. By installing and running a virus-infected program received via email. This is the most common way for a virus to spread, but by following a few simple precautions, you can easily avoid being infected, even without the use of specialised virus protection software..

Email attachments are used to send legitimate documents and pictures with emails. These are usually shown by a paperclip symbol next to the received email. Unfortunately email attachments can also contain viruses. You cannot get a virus just by reading an email - you have to open the attachment. It is therefore important to be able to differentiate between harmless and malicious attachments.

Be cautious of any email with an attachment, even if it appears to be from someone you know. Virus-infected computers will often fake the sender's address, so an email appearing to come from your friend may actually contain a virus attachment.

Check carefully the type of attachment an email contains. Your computer should display a warning box, asking you to confirm whether you want to open or save an attachment. To check an attachment, click once on the paperclip symbol in your email, then on the name of the attached file. A warning box will display the name of the attached file. Note carefully the ending of the filename (the last three letters, preceded by a dot). This is known as the file extension and determines the type of file that has been attached to your email.

Please note: some virus file names may have a double extension, e.g. snowhite.doc.scr It is the last three letters that count ! In this case the virus creator is trying to fool you into thinking this file is a harmless word document but in actual fact it is a Windows script file containing a virus. Others may use a lot of blank spaces in order to hide the real file extension e.g. invoice.txt                                  .scr

If you are not sure about what type of attachment it is, do not open it. Delete the whole email. If you think it may be genuine, confirm with the sender that they did indeed send you the email before opening the attachment.

Virus Hoaxes

These are very common. You will receive a harmless email, warning you that a new virus has been found. This email may be from someone you know and it will ask you to forward the warning to everyone else. Sometimes it may also ask you to delete a file from your computer which it claims is infected. This type of message is a HOAX. Usually there is no such virus and the hoax perpetrators are merely trying to cause confusion and panic people into thinking they have been infected. Do NOT forward this message to anyone and do NOT delete any files from your computer !

As a rule, any email that asks you to forward it to everyone you know is usually a scam of some kind, a chain letter or an advertising stunt. Ignore it and DO NOT forward it to anyone.

Where to look for help

If you suspect you have been infected with a virus, DO NOT start your email program - not even to read incoming emails. Many viruses can spread by sending copies of themselves to recipients from your address book without you knowing ! You can use Internet Explorer to look at one of the official sites listed below that can help you with detecting and removing viruses.

You can also perform an on-line virus check on your computer. This will find and delete any infected files. Go to http://housecall.antivirus.com/housecall/start_corp.asp and follow the instructions. NOTE: this program takes quite a long time to check your computer - be patient.