The first rule of email privacy: Unless encrypted, email is never really private. - Always keep this in mind when composing email messages. Email is easily hacked so pretend that every email you send will be featured on the front page of your local newspaper and you should be okay.
Keep a short leash on your main email account. - Most people are beginning to understand that you should only give out your main email account to those you trust. To take this approach a step further, consider creating temporary email accounts that forward all messages to your main account. Every six months create a new temporary account and delete the existing one. Using this method you’ll never have to worry about whether or not that newsletter you signed up for came with a free side order of all-you-can-eat SPAM.
Use a contact form on your website. - Linking directly to email accounts on your website in plain text format is an open invitation for email harvesters to acquire your email addresses. This quite often results in getting your addresses added to a list that is eventually sold to spammers and the barrage of junk email ensues. Contact forms, if done properly, hide your email addresses from prying eyes and keep your email addresses out of the hands of spammers. If you still feel the need to list email accounts on your website, it is advisable to use temporary accounts as mentioned above so junk mail is kept to a minimum.
Ignore “unsubscribe” pleas. - You should never attempt to unsubscribe from any list that you did not explicitly subscribe to. This little trick is a sneaky way of finding out if you are actively using your email account and unsubscribing will only end up netting you more junk mail since spammers know there is a real live human being at the other end. Simply delete junk messages without unsubscribing and move on.
Configure your email client to read and send email in plain text format. - Phishing, a term used to describe identity theft attempts via email, is much harder to accomplish within a plain text email. Furthermore, if given the choice, elect to receive any subscription emails such as newsletters in plain text format as well.
Stop forwarding chain letters. - Alarmingly, nine out of every ten computer viruses are spread via email. Chain letters provide very few legitimate purposes and often serve to propagate the spread of worms, viruses, etc. As these messages are often based on hoaxes to begin with, they should be treated as SPAM and sent straight to the bit bucket!
Sign your outgoing email messages with a digital signature. - Digital signatures offer a way to help recipients determine the legitimacy of the sender. In addition, adding a digital signature prevents the message from being altered as the signature would break. Authenticity is often important in business correspondence as you may be waiting for important data that you must be certain is arriving unaltered from the proper source.
Use Blind Carbon Copy (BCC) when sending to multiple recipients. - Using the BCC field, in place of the Carbon Copy (CC) field in your email client, hides the list of recipients on each message delivered and keeps the members of your list private. This is often desirable when the members of the list do not know each other or if they have no need to know the actual distribution list.
Attach files carefully. - Whenever possible choose to attach file types that are less prone to malicious activity. For example, Microsoft Word documents (.doc files) are vulnerable to macro viruses so converting to a safer format before attaching is a good idea. Such formats include Adobe’s Portable Document Format (.pdf) or Microsoft’s Rich Text Format (.rtf).
Choose a secure password. - All attempts to keep your email secure are worthless if you use a weak password for your account. Never use simple passwords or passwords that are easy to guess. Instead choose a password that is at least eight characters long, contains both letters and numbers, and is as meaningless as possible. Strong passwords are the basis for any good security implementation and serve to thwart hackers in their attempts to compromise your systems.