You’ve probably read about computer viruses in the papers, or increasingly likely, you’ve had your own computer infected by a virus. This article aims to show you how to keep your system secure.
First of all, ensure that you never open any file from an anonymous person. This includes attachments in e-mail messages. By default, Windows hides the file extension and so a virus writer may exploit and give a file a double-barrelled extension to make it look like, say, a JPEG image when in fact it’s an EXE file. Don’t even open a suspicious looking e-mail message.
By far the best defence that you have is an on-access anti-virus program. This works by intercepting all file types which could potentially be a virus and checking them before letting you run them. While in the past this used to cause delays in file access, computer speeds have become so high and the software developers have become so good that the delay isn’t even noticeable (except on very specific system configurations).
While the anti-virus writers are getting better, so too are the virus writers (although they are usually sad girlfriend-less school-boys who have nothing better to do). This means that the software which was installed on your computer in 1999 is practically useless now. This is because it cannot detect viruses written before after it was. The chances are that the viruses which it can detect have actually died out and so you basically have no protection.
However, you don’t have to update your software by going to a store and buying a new boxed copy, you simply log onto the Internet and either let the software update itself, or go to the developer’s web site and download the updates, usually known as “DAT files” or “Virus Definitions”.
Here are some addresses for common anti-virus software:
Norton AntiVirus - http://www.norton.com
McAfee VirusScan - http://www.mcafeeathome.com or http://www.mcafee.com
Dr Solomons AV - http://www.nai.com
AVG Anti-Virus - http://www.grisoft.com
ThunderByte AntiVirus - discontinued - now Norman Virus Control
Norman Virus Control - http://www.norman.com
Trend PC-Cillin - http://www.antivirus.com
Kaspersky AntiVirus (AVP) - http://www.kapersky.com
Quick Heal - http://www.quickheal.com
Sophos AV - http://www.sophos.com
Panda AV - http://www.pandasoftware.com
F-Prot - http://www.f-prot.com
eTrust InoculateIT - http://antivirus.cai.com
However, various anti-virus (hereafter AV) companies offer different periods for updates. Some, give a year of free updates, others for the life of the product (i.e. until the next version comes out) and others just keep putting them out.
If you do need to upgrade your whole software though, don’t worry it’s usually a fairly pain-less process. Newer software will usually have better features too. For example, Norton AV 2002 now intercepts incoming and outgoing e-mail messages to see whether they contain a virus. This way, you can be sure that you’re not going to send a virus on your computer to anyone else. Luckily if you’re running up to date virus definitions (and by this I mean checking at least once a week for update) you shouldn’t get a virus in the first place.
If you’re upgrading your software, just make sure that you know that it supports your chosen operating system. For example, with the retail versions of McAfee VirusScan, you must use version 6 if you intend to install it on Windows XP. Since AV is works on such a low level, if it doesn’t mention your operating system on the box, then don’t buy it because you risk causing system instability.
Outlook Express Tips
Now, you’ve got your AV software set up, you want to ensure that you’ve got the absolute best protection. If you’re using Outlook Express with the default settings, you’re running the risk of getting infected with a virus.
Start up Outlook Express, then go into your Inbox. Now, go to the View menu and select Layout
Ensure that Show Preview Pane is unchecked. This will stop messages from automatically being displayed when you click on them. The reason for doing this is that the newest message is always selected when you start Outlook Express and if it contains a virus, this will be run in the preview pane. While this can be a bit more inconvenient, you will probably get used to it after a week or so of use.
Next, we need to change the security zone settings. While still in Outlook Express, go to the Tools menu and select Options. Go to the Security tab and make sure that Restricted sites zone (more secure) is selected.
Now, right click on Internet Explorer on the desktop and choose Internet Options (or with an Internet Explorer window open go to Tools and select Internet Options). Click on the Security tab and click on Restricted sites, and click Custom Level. Set everything to Disable (all ActiveX should be disabled, Downloads should be disabled, Java should be set to Disable Java and especially Active Scripting).
That should cover just about everything. The only other thing is Spyware. While these aren’t technically viruses and aren’t illegal, they can be rather sneaky. They monitor your browsing habits and report information back to advertising companies. Spyware now comes with many pieces of shareware, which leads to many people avoiding shareware. However, there is something you can do to stop these small programs from reporting information.
The solution is a Firewall. Firewalls have been around for a long time in the corporate world, where company networks could hold confidential information. However, when always-on broadband connections and Internet banking started to become popular, leading software companies developed consumer versions of their firewall programs. However, these have become very popular, even with 56K dial-up users now due to spyware (aka “Personalised Advertising”).
When you install firewall software, it will often look for a list of Internet-enabled programs on your computer. You can then tell it which programs are pre-approved for access to the Internet (for example Internet Explorer and Outlook Express). You then “train” the firewall when additional software attempts to access the Internet.
There is an excellent free firewall available called Zone Alarm (http://www.zonelabs.com) along with others which are commonly bundled with AV software, for example McAfee Firewall 3.0 bundled with VirusScan 6.0.
Zone Alarm - http://www.zonelabs.com
McAfee Firewall - http://www.mcafeeathome.com
Norton Personal Firewall - http://www.norton.com
BlackICE Defender - http://www.networkice.com
The choice of which you choose is up to you.
Well, I hope that you found this article interesting. If you have any further questions, feel free to e-mail me. As far as I’m aware, all information contained on this page is correct at the time of writing (March 2002). If any companies want their product names removing from this page then let me know. Similarly, if any companies wish to have their software added to these lists, then again please e-mail me.