Virus Protection

Preventing viruses from attacking your system is a mixture of commonsense reasoning with some down-to-earth practical precautions, mixed with the use of one or more anti-virus packages to routinely check your system for infection. The level of protection you decide upon will depend on how much you would feel the loss of data if you were infected, and how much time you would spend cleaning up after the infection. A business user with many PCs and business-critical data at stake will be prepared to spend far more on A/V protection than the average home user, because the sums at risk are so much greater. Using appropriate anti-virus protection is at least as important in preventing catastrophic data loss as the backups you make routinely. (You *do* make backups, don't you?)

Commonsense Precautions

• Never use pirate software or warez - not only is it illegal, but you don't know where it's been, or what might be lurking in there.
• Always scan all freeware and shareware before use, even when it comes from what appears to be a reputable source.
• Always scan all Internet downloads before installing and running, even when they appear to be from a reliable archive site.
• Ensure that you scan all floppy disks you are given before use. This includes shared disks, pre-formatted blank disks and even distribution disks with original software on. Write-protect disks when not in use to prevent accidental infection.
• Never run programs attached to email before scanning, even when you are sure they come from a trusted source. Save them and scan them before running or installing them.
• Always scan any document attached to email before opening, or save the attachment and turn off macro features in the program you are using before opening it.
• CD-ROMs and CD-RW disks should be scanned if your software allows it, but you will not be able to disinfect if you find a virus.
• Make sure that you always have an updated signature file for your A/V package. This will ensure optimal A/V protection with signature-based A/V software.
• Use more than one A/V package if you can, as there is a tendency for A/V packages to detect some viruses and miss others. Using multiple packages increases your chance of detecting something nasty before the infection spreads.
• Make sure that you back up your data regularly and that you can restore successfully. Ensure that you have a virus-free boot disk to boot from in case of infection, and that you also have virus-free disks containing any tools or device drivers you need to recover your data and rebuild your system.

Using an Anti-Virus Package

If you haven't got an anti-virus package already, then you should. There are many around, both free and commercial. Try F-Prot if you need a free virus package, or get hold of free evaluation copies of commercial products such as Symantec's Norton Anti-Virus, McAfee's VirusScan, or ThunderByte and then buy the one you prefer. If you are protecting corporate data, you need to look at some of the disk control mechanisms available such as Reflex Magnetic's DiskNet, and also scan incoming email using a product such as MimeSweeper. There are many alternative products on the market, and you need to assess your degree of risk before evaluating the products to find one that suits you.
Once you have your anti-virus package, make sure that your machine is virus-free *before* installing the package, and then make sure that the signature file is always up to date. Some packages will automatically attach to the Internet at periodic intervals to download the latest signature file, but if you have read this far in the book you might have your own ideas about the wisdom of that, and would prefer to download the signature file yourself.