Sunday 22nd April at 5.03pm

How Green is your PC?

There's no getting around it: computers aren't exactly the world's most eco-friendly devices. They guzzle materials and electricity and they seem to need replacing every couple of years as technology advances and they become obsolete. The environmental campaigning group Greenpeace International has compiled the latest edition of its quarterly report which ranks the world's greenest electronics companies. Iza Kruszewska, Greenpeace's Toxic's Campaigner joins Adam on this week's programme to reveal the best and worst companies.

Black Hats and White Hats

We may not be aware of it but there's a war raging in cyberspace between the forces of good and evil. On the dark side are the 'black hats', the hackers who break into company networks and domestic PCs to steal information or wreak havoc. Ranged against them are the 'white hats', the experts who spot and close potential security loopholes before they're exploited. The University of Abertay in Dundee has recently launched the UK's first degree in 'ethical hacking' to train the next generation of 'white hats'. Adam speaks to Dr. Allan MacLeod from Abertay about the battle for computer security.

Link: University of Abertay Ethical Hacking Course

Timewasting

What Was I Looking For? The latest term for wasting time on the internet is 'wilfing' and a recent poll discovered that more than two thirds of the UK's 37 million internet users admit to wilfing as they log on in search of one thing and end looking at a completely different website. So now it's official that the internet is the greatest waste of time ever invented, mousemat asked Rhodri Marsden who runs The Independent's Cyberclinic to give us his thoughts on killing time in cyberspace.

Rhodri's website: timewasting.net

Q&A

Part One:

Our first question comes from Steve Daly:

Q: "I have an 18 month old Hewlett Packard PC and I have eScan security suite. Once or twice a month the Windows yellow shield comes up in the system tray with the message 'Downloads are ready'. Now, I have not set up auto Windows updates and when I looked it was off. I understand the yellow shield can be a warning. Could the manufacturer, HP, have somehow enabled these auto updates?

I have also had unsolicited e-mails offering me items which I have mentioned in my emails - as one item was a now obsolete floppy disc drive I wondered if I can have spyware aboard? The eScan software has an anti-spyware feature."

Simon Says: There are a variety of auto-update options you can select. The one I usually recommend is 'Automatically Download and Install' so that you don't miss any critical updates. However, you can set the system to notify you when updates are available without them being automatically downloaded. Very occasionally updates can cause more problems than they solve but this is rare and generally the advantages of automatic downloads from Microsoft outweigh the disadvantages.

As far as the question about possible spyware is concerned, the explanation for the unsolicited e-mails may well be that your e-mail address has been picked up from the internet by someone who has seen that you're selling computer equipment rather than by spyware. However, it's worth checking that the anti-spyware protection on your PC is up to date.

Part Two:

Our second query comes from Michael Crook in Carmarthen in response to Simon's advice on electrical surge protection a couple of weeks ago:

Q: "The PC Doctor mentioned that surges can come via the phone line in addition to via the power supply and that recently lightning in Pembokeshire had caused such damage to many people's PCs via the phone lines. The occurence was more widespread than just Pembrokeshire as I was hit here in Carmarthen. The Doctor recommended therefore buying a 'gang socket extension' which had surge protection for both power supply and phone line. At the time of the strike I already had power supply protection so I went out and bought an extension which had the 'phone line surge' protection, and a £2000 warranty!

However, upon getting home I removed the packaging and read the product instruction leaflet only to discover that "This device is not a lightning arrester and will not protect equipment against lightning strikes." In the circumstances I contacted the product company's head office who told me that neither they or any other company supplied a device for protecting a home PC against lightning, as any such device would have to be the size of a house or greater. Perhaps the PC Doctor might like to comment"

Simon Says: The core of the problem here is the terminology. It's almost impossible to protect a computer against a direct lightning strike. If the building you're in is struck then there's very little you can do to protect electronic equipment inside the house.

However, surge filters or surge protectors can defend you against 'collateral damage' if there's a lightning strike in the vicinity, say a mile or two away. These strikes can be conducted through phone lines or the mains and unless you have surge filters in place your PC could be damaged. In the event of a current overload from a nearby lightning strike the filter itself absorbs the current and 'dies' but your computer and modem are protected.

Any problems for PC Doctor Simon Zerafa can be e-mailed to mousemat@bbc.co.uk

The BBC is not responsible for the content of external websites