Secure your PC

-All about Spam

 

What is Spam?

  - It's a rare computer user who hasn't been bothered by Spam at some stage. By Spam, we mean unsolicited emails that try to sell you things of a dubious nature that you certainly didn't ask for and, in all probability, don't need. Everybody hates spam. It can clog up your email box, threaten the security of your PC, try to trick you into opening dangerous attachments, and even render the mail box entirely unusable. Here at Home and Learn, we've had to close down many email addresses due to spam. (We've only ever met one person who liked spam. This was a pensioner, new to email, who complained that something was blocking her advertisments. She wanted to know how she could get them back!)

How do the spammers get hold of my email address?

Spam can come from a wide variety of sources, and the spammers have many techniques to get hold of your email address. Here's just a few:

> From a web page
If you have ever posted to an online, public forum, and left your email address on the page, then it will almost certainly end up in the hands of the spammers. If you have your own website, and include your email address in plain text, then that will also get stolen by the spammers. In fact, anywhere on the web where you leave your email address is a source for the spammers. If you can see it, so can they.

The way they get the address is by something called harvesting. This is done with a piece of software called a Spider. The sole job of the Spider is to trawl through website looking for email addresses. Once the spammer has enough addresses, he (they are usally "he's") can sell them to third parties, and other spammers.

> From an infected PC.
A lot of viruses these days contain code to trawl through your email address book. These will then be sent to the spammer. If you have sent an email to somebody who is infected, and that person has you in his/her address book, then your address will be sent to the spammer.

> From YOUR infected PC
If you have a virus, the chances are that it will contain code to control your email. It will then contact another computer and receive a list of instructions, and email addresses. These instruction say something like, "Send the following email to this list of addresses". Your PC won't be sending out thousands of emails, but just a few. This is because your PC is just one of many thousand that are controlled by the same spammer (called a botnet). If your computer sends out just, say, 100 emails a day, then 100 times 1000 computers that the spammer controls totals 100,000 emails a day. If the spammer controls 10,000 computers then that's a million emails a day he can send out!

> Trial and Error
if you have an email address based on your name, and if your name is quite a common one, then the spammer will simply send out email trying to guess the first part. For example, suppose the end of your email address was "smith.co.uk" And you added "John" to the start, your email address would be easy to guess, and you'd have a very busy inbox indeed! If it was "john12_KJ876@smith.co.uk", it's unlikely the spammers could guess the first part.

Worst case scenarios

If your computer is infected, there could be another nasty side-effect - YOU get banned! Because your computer has been indentifed as sending out spam, you may well receive a message from your service provider telling you that your account has been suspended. You then have to go to the trouble of contacting your service provider, telling them that you're not a spammer, and asking what to do to get off their "bad books".

A more likely scenario is that your email gets bounced back to you by someone like SpamCop. The email will identify your IP address, and let you know that you're on a blacklist. SpamCop will keep you on the blacklist until it receives no more spam from your IP address in a 24 hour period. (It may not be your IP address but the address of your email servers. In which case, there's nothing you can do about it but notify your service provider. Your service provider will then totally ignore your call, and heap the blame on you!)

How to Defeat Spam

You can defeat spam (well, most of it). Here's a few ways.

• Don't post your email address on a web page, unless you're disguising it in some way. As an example, an email address in this format is very difficult for a Spider to read, but quite easy for a human:

firstBit @ co. uk. hanlrn (re-arange the ending)

• Be wary of giving your email address to websites. Ask yourself, is there a privacy statement anywhere on the site? Can you easily opt-out if they send an email or newsletter to you? Do you trust them?

• Never reply to a email sent to you by a spammer. If you do, you're telling the spammer that the email address is live and active - the very thing that he was looking for! (Remember: the spammer probably bought his list off someone else, and has no idea whether an address is active or not.)

• Careful when opening attachments. Save the attachment to your hard-drive first, scan with your (up-to-date) Anti Virus software, and only then consider opening it. If you weren't expecting an email with an attachment, it's safer to just delete the entire email!

• Set your email software to view message as text and NOT as HTML. In Outlook Express you can do this by clicking Tools > Options from them menu bar. From the Options dialogue box, click the Read tab. Put a tick in the box "Read all messages in plain text". The reason you'd want to do this is because HTML emails can be very helpful to spammers. They insert an image that tells them the email has been read, and thus that it's a live email box.

• Consider getting some Anti-Spam software. The best of these are very good at detecing spam from the genuine emails. Here's two that Computer Shopper recommended in a recent review. (Dec 2006)
  • Allume SpamCatcher 4
  • Cloudmark

These both got 5 stars out of 5 in the review. The second one is only for Outlook or Outlook Express users. (Mcafee anti-spam got 4 stars out of 5, incidentally, and Norton only got 2!)

A good free anti-spam solution is SpamPal. This got 4 out of 5 stars, but Computer Shopper noted that it was a bit "clunky to set up".

But we recommend you start with the free software first, and test it out. If it's not catching at least 90% of spam coming in, then uninstall it and try something else!