Klez may not be a word many people are familiar with but it is the name given to one of the most annoying, destructive and vicious email viruses that has been seen for some time.

It is very good at disguising itself as something else. It arrives in your inbox using spoofed From address, so it often appear to be a message from a friend or colleague.

It uses a very large number Subject line messages, so it is impossible to avoid as you might usually do by setting your mail to automatically bin messages with specific subject keywords. It sends a wide variety of attachments, all of them containing another copy of the virus to enable it to spread ever further.

Klez has reached the stage where, according to some estimates, it is infecting one every 300 email messages sent.

So there's a very good chance that a copy of it will be sent you sooner or later.

As with so many email viruses, Klez takes advantage of the popularity of Windows, Outlook and Outlook Express, using holes in the security systems infect new machines. If you using these software packages, make sure you take sensible steps to avoid being infected.

Don't use the auto-preview feature, which lets you read email without actually opening it as this can allow dangerous code to be run without you noticing. Above all, get some anti-virus software and keep up to date. You don't have to pay for this, since some of the free anti-virus packages are perfectly good for most users.

Either configure it to autoupdate itself (most programmes can do this over the internet)

remember to check for updates yourself as regularly as you can.

Klez is not the only internet annoyance that begins with the letter The other is a country, Korea.

More specifically, the small number of individuals who use the Korean domain space for the sending of millions of spam messages.

These are not necessarily Korean citizens but, wherever in the world they are located, they are using the .kr address space to flood other people with unwanted advertising. Usually these spams are in Korean, so the spams just look like a garbled mess.

Thankfully, the authorities are taking action.

Earlier this year, the Korean Information Security Agency (www.kisa.or.kr) slapped heavy fines on two local companies, an adult TV channel and a computer design centre, for spamming.