- Stay Up-To-Date - Most virus infections don't have to happen. Software vulnerabilities that the viruses exploit usually already have patches available by the time the virus reaches a computer. The problem? The user simply failed to install the latest patches and updates that would have prevented the infection in the first place. The solution is simple: enable automatic updates, and visit Windows Update periodically. Keeping Windows and other software up-to-date is the most important (and easiest) thing you can do to protect your computer.
- Get Educated - To be blunt, all the protection in the world won't save you from yourself. Don't open attachments that you aren't positive are okay. Don't fall for phishing scams. Don't click on links in email that you aren't positive are safe. Don't install "free" software without checking it out first - many "free" packages are free because they come loaded with spyware, adware and worse. When visiting a web site, did you get a pop-up asking if it's ok to install some software you're not sure of because you've never heard of it? Don't say "OK". Not sure about some security warning you've been given? Don't ignore it. Choose strong passwords, and don't share them with others.
- Use a Firewall - A firewall is a piece of software or hardware that sits between your computer and the Internet and only allows certain types of traffic to crossl. For example, a firewall may allow checking email and browsing the web, but disallow things that are commonly not as useful such as RPC or "Remote Procedure Calls".
- Virus Scan - Sometimes, typically via email, virii are able to cross the firewall and get to your computer anyway. A virus scanner will locate and remove them from your hard disk. A real time virus scanner will notice them as they arrive, even before they hit the disk, but at the cost of slowing down your machine a little. Important: because new virii are arriving every day, it's important to keep your virus definitions up-to-date. Be sure to enable the scanning software's automatic-update feature and have it do so every day.
- Kill Spyware - Spyware is similar to virii in that they arrive unexpected and unannounced and proceed to do something undesired. Normally spyware is relatively benign from a safety perspective, but it can violate your privacy by tracking the web sites you visit, or add "features" to your system that you didn't ask for. The worst offenders are spyware that hijack normal functions for themselves. For example, some like to redirect your web searches to other sites to try and sell you something. Of course some spyware is so poorly written that it might as well be a virus, given how unstable it can make your system. The good news is that, like virus scanners, there are spyware scanners that will locate and remove the offending software.
- Secure Your Mobile Connection - if you're traveling and using internet hot spots, free Wifi or internet cafes, you must take extra precautions. Make sure that your web email access is via secure (https) connections, or that your regular mail is over an encrypted connection as well. Don't let people "shoulder surf" and steal your password by watching you type it in a public place. Make sure your home Wifi has WEP or, preferably WPA security enabled if anyone can drive or walk within range.
- Don't forget the physical - an old computer adage is that "if it's not physically secure, it's not secure." All of the precautions I've listed above are pointless if other people can get at your computer. They may not follow the safety rules I've laid out. A thief can easily get at all the unencrypted data on your computer if they can physically get to it. The common scenario is a laptop being stolen, but there are many reports of people who've been burned because a family member or roommate accessed their computer without their knowledge.
It all might seem overwhelming, but it's not nearly as overwhelming as an actual security problem if and when it happens to you. While we might want it to be otherwise, the practical reality of the internet, and computing today, is that we each must take responsibility for our own security online.