Microsoft released another patch for its Internet Explorer browser last week, but some security experts are already claiming it doesn't fully protect users from malicious hackers from breaking into even patched Windows machines.

Industry studies have shown that as many as half of the people hooked up to broadband Internet connections don't have a firewall or other protective measures. And an even larger percentage of machines have various forms of so-called "spyware" infecting their operating systems. While owners of Macintosh and Linux computers aren't entirely safe from problems, the majority of computer users use a Windows operating system, and that is where most of the problems occur.

So what is a computer user to do?

These seven suggestions will help lock down your computer. There's no guarantee this will protect you in every situation, but it will take care of many of the more obvious problems. And even better, all of these suggestions are free.

1. Run Windows Update
Yes, this is an obvious one, but a surprising number of people don't bother to take advantage of Microsoft's various software updates. Go to the URL listed below, or if you are running Internet Explorer, go to the "tools" link at the top of the browser and select "Windows update." When you get to the page, click "scan for updates" and the Web site will look at your computer and suggest updates and patches that you should download.

Update Link: http://v4.windowsupdate.microsoft.com/en/default.asp

2. Get A Firewall
A firewall is software that sits between your computer and the Internet and helps block unauthorized people from accessing your computer. There are plenty of programs to choose from, but my personal favorite is Zone Alarm. It's free, easy to configure and does a good job of protecting your computer.

I do have a couple of suggestions, which may help you get the most out of Zone Alarm. When you install it, you can choose the option that allows access to the Internet for the most common pieces of software (your browser, media player, etc). But also choose the setting that forces you to approve each additional piece of software's ability to access the Internet. This gives you the chance to see if any Trojan horses or hidden programs are already infecting your computer.

Not sure if a program is good or bad? Write down the name and plug it into your favorite search engine. Odds are good that you'll easily find out all you need to know about the software and whether or not it should be on your computer.

Zone Alarm
http://www.zonelabs.com
Click the "downloads" link and choose the basic, free version.

3. Rid Your Computer Of Adware And Spyware
Adware and spyware are generic names for programs that sit on your computer and do everything from track your activities to offer extra pop-up advertising windows. Many of them aren't dangerous per se, but do slow down the performance of your computer.

But there is some software that is much more malevolent. Trojan software, as you can guess from the name, sneaks onto your computer and hijacks it for other purposes. Some of them send spam; some of them dial pornography sites overseas when you're offline. Most of them can be eliminated from your computer, but some are almost impossible to eradicate.

Because there are so many things to watch for, it usually makes sense to download both of these programs because no one program can find everything.

The following free software will help, but if you're already infected with the worst variations, you may need to take your computer to a professional.

Suggested software:
Spybot Search And Destroy
http://www.safer-networking.org/index.php?page=download

Ad-Aware
http://www.lavasoftusa.com

4. Think Twice Before You Download A Program
There are a number of seemingly innocent programs that offer to do everything from provide weather information to automatically fix the time on your computer. Many of them are perfectly fine, but the ones that aren't will also fill your computer with enough pop-up windows to drive anyone nuts.

Use the search engines. Before you download something, find out what other people are saying about the program. If it's good, you'll find out quickly. And if it's up to no good, you'll be glad you took the time for a bit of preventive research.

5. Find Out What's Lurking On Your Computer
After you have run the software above, find out what else may be lurking on your computer. Pest Patrol is a great piece of software, and well worth the $40 purchase price. But the company also has a free Web site that will search every cranny of your PC and let you know which programs are hiding out of sight.

After you get the results, you can once again use the search engines to uncover the best way to remove them. The three categories that you should most worried about are "Trojans" (which can take over your computer), "key loggers," (which can capture your passwords and other information) and "browser hijackers, which can do things such as set your browser to automatically visit an adult-oriented Web site.

Pest Scan
http://www.pestscan.com

6. Consider Trying Another Browser
About 95 percent of all Windows users also use the Internet Explorer browser. And that's not just because it's the default browser on nearly every new computer. It's also due to the fact that until recently, it was the best choice for most computer owners.

But with the recent release of the newest version of the free browser Firefox, the average user has another, better choice than IE.

Firefox isn't as susceptible to many of the problems recently associated with Microsoft's browser, and it also offers a number of improvements, including a built-in pop-up blocker and tabbed windows. Even better, you can easily import all of your bookmarks and other settings from your current browser.

There is one slight caveat. A few Web sites don't work very well with Firefox. Either they look a bit off or simply don't work at all. If you do run across one of those, it's easy to quickly open IE. But for nearly all situations, Firefox is a fine alternative.

Another browser alternative is Opera, which has both a paid and free version. The free version comes with an ad banner, but is still worth a look.

Firefox
http://www.mozilla.org/products/firefox

Opera
http://www.opera.com

7. Be Careful With Your E-Mail
Most Windows users have either Outlook or Outlook Express as their e-mail client, and the easiest way to say this is that you have to be very careful. Virus writers love Outlook because it is so easy to trick the casual computer use into opening or downloading a virus.

There's not enough space here to get into all of the things you should consider, but here are a couple of suggestions that will help protect you.

a. Don't use the "preview pane." Trust me, it's only going to make your spam problem much worse.

b. Think at least three times before downloading or opening a picture or program, even if it's from someone you know. It's easy for programs to pretend they are coming from someone you know and trust.

c. Adjust your settings to become more secure. One place to start is the link below, which gives you a good overview of the problem.

http://www.slipstick.com/outlook/antivirus.htm

While the above suggestions won't cover every situation, they will take care of the obvious problems, which is the amount of protection that works for most people.