• Only use a well-known brand Anti-Virus software to make sure it’s reliable. A decent programme will scan your files for changes to the size of your files, well-known viruses, unusual or suspect email attachments and more. It does this by running at all times on your computer.
• Be wary of any attachments sent to you, particularly from unknown email addresses. Once you have antivirus, you will then be able to scan attachments before they run.
• Check attachments even if they are from an email address you recognize, as malicious code, like Trojan horses, can invade your system by appearing to be from a friendly source.
• Make sure you set up your anti-virus software so that it automatically runs at all times. This will so that you have back-up protection in case you forget to scan an attachment, or decide not to.
• Update your anti-virus software frequently, though this should be part of the package you purchase. This is because new viruses, worms, and Trojan horses come out all the time, and so these can pass by software if it is not current.
• Watch what you download from the Web. Some unreliable or unknown sources such as sites that you haven't heard of may provide viruses for your computer. Other things you should avoid downloading unnecessarily are games and wallpaper, as well as files ending with ‘.exe’ or ‘.com’. Remember, you can scan anything you wish to download to make doubly sure.
• If you are using a CD or DVD when you’re on your computer, remove it when you shut the machine off or the computer may attempt to boot from the CD, thereby freeing any viruses on the disc.
• Finally, think logically. If you're unsure about an email or strange-looking attachment, delete it.

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