Here are the most common ways you might pick up a virus
(And some common practices to avoid them)

1 - Infected email attachment

Opening an infected attachment is still the front runner for catching a virus. Although email sent to Netstar servers are checked by two level Anti-Virus systems, remember that a successful virus author is always ahead of the anti-virus software. Think carefully before opening any email with an exciting title and a fun-sounding attachment.

2 - HTML email scripts

You don’t have to open an attachment for an email to be harmful. HTML-formatted email can contain  harmful scripts that may be opened by Outlook Express. Receiving messages in plain text helps to protect your PC, but disables some functions. To make the change, select Tools -> Options. Move to the Read tab of the Options dialog and Put a tick in the box marked ‘Read all messages in plain text’.

3 - Infected files

If there’s an infected file on your system, the chances are that it will infect your whole PC. This is also true for files on network drives or removable media. So you can be re-infected by a virus that you think you have already removed if its parent files still exist on your PC. Disinfect all the resources that you use should you contract a virus to prevent re-infection.

4 - Unsafe downloads

Downloading a file from an unsafe source is still a top way to catch a virus. If in doubt, don’t download it. Make a point of scanning new downloads with an anti-virus even if you’re confident of their origin.

5 - Drive-by downloads

A drive-by download is one that occurs without your consent and often without your knowledge. It can be triggered by visiting the host Web site or by viewing an HTML-formatted email. The first you may know of it is when your PC behaves oddly or your Net connection becomes much less effective. Install SP2 or by hike up the security settings in your browser to prevent ActiveX components from launching.

From your Internet Explorer go to: Tools > Internet Options > Security > Custom level. In here you can adjust your security level to your liking.

6 - Backdoors and Windows exploits

A backdoor may be installed on your system by another virus. It may also have been planted in an application. It provides a way to access your system, usually remotely, while avoiding normal authentication procedures. Once one virus has opened a backdoor or taken advantage of a Windows vulnerability, it enables your PC to be infected by a range of other viruses.

The best practice to be sure that you are safe, is to have a good Firewall and Anti-Virus pair of software.
 

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