Ever wonder why you get viruses and junk mail? Are you sick of it? A US computer expert explains how you could be part of the problem — and what to do about it

Half of us don't know how to correctly forward to others an email we have received — and our actions can have serious repercussions.

Every time you forward an email, information is still attached to it from whoever sent it to you, and perhaps people who sent it to them — namely the email addresses and names. As messages get forwarded on, the list of addresses builds, and builds, and builds. . . All it takes is for one of them to pick up a virus and their computer can infect every subsequent recipient.

How do you stop it? Follow this step-by-step guide:

1. When you forward an email, DELETE all of the other addresses that appear at the top of the message. You MUST click the 'Forward' button first to give you full editing capabilities on the body and headers of the message. Then highlight the addresses and delete them. It only takes a moment.

2. Whenever you send an email to more than one person, do NOT use the 'To:' or 'Cc:' fields for adding extra email addresses, always use the 'BCC:' (blind carbon copy) field. This way the people you send to will only see their own email address. When you send to BCC: your message will automatically say 'Undisclosed Recipients' in the 'To:' field of those who receive it.

3. Remove any 'FW:' in the subject line. Even re-name the subject if you wish.

4. ALWAYS hit your Forward button from the actual email you are reading. Ever get those e-mails that you have to open ten pages to read the one page with the information on it? By forwarding from the actual page you wish someone to view, you stop them from having to open many emails just to see what you sent.

5. Have you ever received an email that is a petition? It states a position and asks you to add your name and address and to forward it to ten or fifteen people or to everyone in your address book. The email can be forwarded on and on and can collect thousands of names and email addresses.

A FACT: The completed petition is actually worth a lot of money to a professional spammer because of its wealth of names and email addresses. If you wish to support the petition then send it as your own personal letter. It would also carry more weight as a personal letter than as a laundry list of names and email address. (Actually, if you think about it, who's supposed to send the petition in to whatever cause it supports? And don't believe the ones that say that the email is being traced, it just ain't so!) 

6. Of those that I especially hate, one goes something like this: 'Send this email to ten people and you'll see something great run across your screen.' Or sometimes they'll just tease you by saying something really cute will happen. It ain't gonna happen! Trust me, I'm still seeing some of the same ones that I waited on ten years ago. And I don't let the bad luck ones scare me either, they get trashed.

7. Before you forward an Amber Alert, or a Virus Alert, or some of the other ones floating around nowadays, check them out before you forward them. Most of them are junk mail that's been circling the net for years. Just about everything you receive in an email that is in question can be checked out at Snopes. Go to http://www.snopes.com/ It's really easy to find out if it's 'real' or not. If it's not, don't pass it on.

And finally: Send this email to everyone you know — but strip out my address first, please! My advice is something that definitely should be forwarded...