QUESTION: With all the recent trouble concerning viruses doing damage to even new computers I am not sure if I am doing all that I should be doing to protect my home computer. A few weeks ago, after my virus software had run out, I had a virus or a system crash or something and lost a lot of my stuff. Eventually, with the help of a friend, I got the computer mostly running again but some programs became corrupted and I think I have to re-install them. When I described the things that still won't work to the IT technician where I work he said it sounded like the computer registry had become damaged. I have no idea how to fix the registry and I'm not even sure what it does exactly. My real question to you is what can I do to protect my computer? I am no expert but I can follow directions pretty well. I can't go through losing my files and e-mails again.

ANSWER: There are four things you must discipline yourself to do if you want to go on enjoying your computer. In order of importance they are:

Maintain the very best anti-virus software you can. Keep it updated, run scans and check e-mails as they go in and out from your e-mail program.

Install and run an ad-ware and spyware checker and removal program such as Ad-Aware 6 or Spy-Bot S&D.

Keep a separate back-up of your data, e-mail and address books and anything else that otherwise exists only in one place.

Finally, keep up with Microsoft Windows Updates. More on that later.

If you only follow one recommendation, this is it!

As I said, the first one is the most important. So important you should view it as a 'must have', and that is the unfailing use of an anti-virus program. The name says it all. But remember, it has to be kept up to date. You have to download the updates regularly or set them to run automatically when you're online. If you let the subscription run out and somebody somewhere devises a new virus you will be vulnerable. Renew the subscription online or go to town and buy a new one in a box. Installed straight out of the box it will only protect your computer against the viruses that were known at the time that the software was manufactured. Once installed on your PC you should go online, register and update to the latest protection devised up to that day. I prefer Norton AntiVirus 2004 because of the logical menus and its track record. You can buy this as a stand-alone product, but read on.

One button tune-up

If you really want to take control, buy Norton SystemWorks 2004. This program is way ahead of its previous iterations. With modern computers, which have spare headroom for processing power and RAM, the various processes carried out by this excellent suite of utilities won't bog down your computer and intrude the way they used to in earlier versions. Also, when you buy NSW2004 it comes with a full year of Norton AntiVirus included. This whole column wouldn't afford enough space to tell you all the things this impressive package does for your PC. Let me just say that it is comprehensive, largely automated and has a One Button tune-up feature that checks several important areas of your operating system, including fixing a faulty registry and is worth the price by itself. By the way, a registry is a central database used to contain information that Windows continually references during operation, such as the applications installed on the computer, what hardware exists on the system, and which inputs are being used. When your registry goes wrong the computer starts to act up.

SystemWorks also cleans out old junk files, optimises hard drive performance with a very impressive Speed Disk utility and even includes a basic version of Roxio's Go Back which can turn the system back to an earlier, better state if something goes wrong as a result of an installation.

Important and free!

The other process, which you should also carry out, is downloading and installing all the relevant Windows Updates available at http://v4.windowsupdate.microsoft.com/en/default.asp. There are three categories and only the Critical Updates are downloaded automatically. The XP and Driver updates you have to deliberately select and download.

I have written about the need to do this many times but many of the people I help still don't do it and as a result their computers remain vulnerable to all sorts of security issues. Many improvements to your Microsoft operating system and new improved features like Windows Media Player and Windows Movie Maker 2 are available there for the free download. When you're looking at the site read the section on the right side of the screen entitled Protect your PC which details three steps designed to help ensure your PC is protected.

No products are perfect but these precautions will go a long way to help you practice safe computing.

QUESTION: I have a lovely handheld PC (Siemens SX56) and have just been able it to set it up to receive email when the thought crossed my mind "what about viruses"? I located an anti virus program for pocket PC at the Symantec (Norton) site. There are a lot of handheld PC users out there who are receiving e-mails, are these machines susceptible to viruses in the same way as the full-sized PCs?

ANSWER: Yes, it can happen, especially since PDA's are becoming increasingly Internet ready, and therefore exposed to everything, good or bad, the Internet contains. There have been cases of viruses in PDA's reported since 2000.

Industry analysts predict that mobile Internet users will grow by 600 million in the next two years and with a market penetration like that there's too much opportunity for mayhem for the virus authors to ignore.

Where are you vulnerable? There are a couple of primary methods that PDA's can pick-up a virus. You might unknowingly download a file from the Web or an infected e-mail attachment and copy it to your PDA by Hotsyncing it. Or you might infect your device when someone beams a file to you.

A wireless worm could be a problem for cell phone users. For example, if you use your cell phone to view content on the Web, the script on the page might send SMS messages to everyone in your in-phone address book. The people who get the message will then be diverted to the same worm-site, which will result in all of their contacts getting the same SMS message. In a short time, this could spread widely,

How can you protect yourself against handheld viruses? Make sure that the full-sized PC's from which you upload and download data are swept and clean. Because handhelds can contract viruses via beaming or the wireless Internet, you should also run an anti-virus solution on your handheld device which will scan its memory for malicious programs. Anti-virus programs designed specifically for handhelds are on offer from the major software providers. Check them out.

James W. Lapsley is the founder of ComputerWorks, specialising in PC repairs, upgrades and advice for the home and small office user. ComputerWorks welcomes your questions and comments. Send your PC questions by e-mail to computerworks@logic.bm or by phone to 293-0992.