To begin, consider only opening and reading a message that passes all of these tests:
The know test—Is the e-mail from someone you know?
The received test—Have you received e-mail from this person before?
The expect test—Were you expecting e-mail with an attachment from this sender?
The sensible test—Does the e-mail subject make sense based on who is sending the e-mail? Would you expect this type of attachment from this person?
The virus test—Does this e-mail contain a virus? To determine this, you need to install and use an anti-virus program.

However, in some businesses it is understood that you will receive E-mail from people you do not know, and so you will have to open all your E-mail that isn't obviously garbage. If you are in this situation, there are a few things you can do to help protect yourself.

To begin, you need to understand the different "types" of E-mail, since they all have different strengths and weaknesses.

One type of E-mail is the "web-based" type, of which a few examples are HotMail, Yahoo Mail, GMail, and the like. The advantages to using this type of E-mail are that the message and all the attachments remain on the mail server until specifically downloaded by you. Most of those E-mail companies will filter out spam and viruses for you before you ever see them. The disadvantage is that you are bombarded with a lot of advertising in the mail window itself, as well as often having their ads attached to your messages. Also, some companies have their own mail server, and have their own domain name, and so they need to use the type of E-mail client that uses POP3 or IMAP so that they can remain "john_doe@big_comapny.com", instead of "john_doe@hotmail.com".

Since the message and the attachment can be viewed BEFORE you download any attachments, you can often tell just by looking if the message and its attachment should be deleted. Should you need to download the attachment, it is recommend that you download the file to an easily found folder, and then before opening it, right-click on the file itself, and choose the "Scan Now" option (description may vary by AntiVirus program). Once the file is scanned successfully, it is safe to open and view it.

The POP3 and IMAP types of E-mail programs are Outlook and Outlook Express, Eudora, Pegasus and the like. These POP3 type mail programs have the advantage of leaving you entirely in control of your message, being able to easily craft different styles, fonts and embedded documents. You can also traditionally send attachments much more easily. Also, the message itself and any attachments that you DO need are always at your fingertips on your PC, even if you are not connected to the Internet. The big disadvantage is that in order to see the message, it and its attachments have to be downloaded to your computer. You will be relying on your computer's AntiVirus program to catch and kill viruses. Should your AntiVirus  program be outdated, it is very likely that infected files WILL get in to your computer.

There are simple safeguards you can take and procedures you can follow that will keep you bug-free with this type of E-mail program.   (cont.)