Malicious Software

While it is true that websites are fast becoming the number one source of security risks to the average user, viruses, worms, trojan horses and their friends are still out there to get. But shoving as much security software onto your computer as you can is not the solution; you need to understand what threats are there, and what you should do to protect yourself from them.

Viruses

Viruses can slow your computer down, steal private information from you, and damage your computer. Unfortunately, antivirus software has a reputation for slowing down your system, so apart from cost and effectiveness, you also have to look at the performance of an antivirus when you pick it.

Antivirus software can be broken down into two obvious categories: free and not free. I have not used an antivirus that you have to pay for since 2007 and I have not suffered a virus attack since. I was sent a virus at the start of the millennium that Norton at the time failed to stop; I also have a friend who around the same time got a virus that actually disabled Norton and thus held the door open for other viruses to come in. The only other virus I have suffered from was the blaster worm, which almost everyone got at the time.

I currently recommend Avast. In my own private benchmarks, my computer turned on faster when using Avast than it did using AVG, another popular antivirus that offers a free version.

If you do want to pay for your software, although that by no means ensures that it is more effective, then I recommend Sophos. I have had only bad experiences with Norton, but I have been informed that their latest version is an improvement.

I recommend keeping an antivirus installed and updated on your computer at all times and just swallowing the performance loss. If you are truly that concerned about performance, then try ClamWin, as it doesn't run in the background but can be used to run a full scan at any time, and updates daily.

Worms

Worms are similar to viruses, except that like real worms they can move around by themselves, and unlike computer viruses, don't need to attach themselves to existing files in order to infect PCs.

Apart from a good and up-to-date antivirus, the best protection from worms is to update your operating system whenever security updates are available.

Firewall

I used to run separate firewall software on Windows XP, but since Vista I have happily relied on the built-in firewall and not suffered for it. I don't recommend running separate firewall software for this reason as I don't believe it is worth the performance loss. If you are behind a router then it will be protecting you too.

Spyware

Spybot is the only dedicated anti-spyware software I have ever consistently used. If you disable the "teatimer" feature, then it will not run in the background consuming resources, but is still always available for you to run a system-scan whenever you like to ensure you haven't picked anything up on your travels. I am happy to report however that since using Avast, Spybot has never found a piece of spyware on my computer other than tracking cookies, which don't worry me.

UAC and other Windows security blemishes

Windows Vista and Windows 7 have two built-in security features that are worthless: User Account Control (UAC) and Windows Defender. According to Sophos, UAC has a 70% chance of not stopping a virus on your computer. So it really isn't worth the annoying pop-ups that it provides, and you should disable it. As for Windows Defender, running a good antivirus like Avast and using msconfig to control your startup programs makes this software essentially redundant, and you should disable this too, first from Control Panel, and then from the Services window, to increase system performance.

Hosts File

Before contacting a server to find out the IP address of a given link, Windows can check its own internal Hosts file to resolve the IP and save time. You can use this to your advantage however if you edit your hosts file to block the IPs of websites that will try to send you malicious software. Thankfully, you don't have to do this yourself; you can download a hosts file periodically from winhelp to avoid accessing websites that have been found by others to be harmful.

The hosts file can also be used to increase system performance; if you manually add all the IP addresses of your favourite websites, then Windows does not have to access any servers in order to resolve the URLs, although your web browser may cache these for you already.