It cannot be emphasised enough how important your computer security is, especially if you've started to build up your business. You literally have your business on your computer. So protect is as best you can. Do this partly by getting the best security software you can afford.

1 Attachments. It could be bad enough opening an email itself which comes from a strange address or with a peculiar subject line. But if it also has an attachment, then it ought to be deleted immediately. You should never open an attachment unless you're expecting one and you know who it's coming from. Even then, make sure you check it for viruses with your own software or with the email service's checking system.

2 Unknown. If you come to a website which is unclear as to its origins, you need to take great care. Maybe it has funny jokes or graphics, they may be there just to give the site time to infect your computer. Also, it may encourage you to send it to friends so it can spread the infection.

3 Turn off. When you're not using your computer, it's best practice to turn it off or disconnect from the internet. This prevents a hacker getting into it while your not attending to it. Hackers can't get into your computer when it's off or not connected to the internet.

4 Boot disk. Make a boot disk to take your computer back to a certain point in time or keep the boot disk you made when setting it up. Also, you can usually have the computer system restore to an earlier set up if it does crash or has a problem.

5 Allow file extensions. Your Windows(TM) system may hide certain file extensions. Try to have file extensions showing so you can see any unusual ones.