Email security guide
This guide is dived into two sections, the first being some guidelines on how to mail safely and the second being reviews about emailprograms and tips on configuring them.
Section One: Mailing Safely
'Trust nothing until proven trustworthy'. Emails from unknown senders are usually spam, contain attachments with malware or are so-called phishing mails. Let's worsen the scenario, even mail sent by people you do know can contain malware, can be phishing mails or can be a hoax. So get a good virusscanner to protect yourself against malware and keep your operating system up to date.
To prevent spam, don't post your email-address at forums/websites. Just like there are 'spiders' and 'bots' (small applications which search the web) for searchengines, to build a database of websites, there are spambots/spiders which crawl the web to find mailaddresses to enter into their spambase. When you register at a forum/website you can use your real address, allways read the privacy statement first. When you need to let other people know where you can be reached, change the format of your address to something like this joeNOSPAM@doe.com. Users will know the need to remove NOSPAM, bots don't.
Never, NEVER, click the 'unsubscribe' button in those mails, you won't be removed from the list but instead you confirm the existence of your address and start receiving more spam.
To finish the 'spam-part' when signing up for a free website, a sweepstake etc. Read the privacy policy and never, when the option is available, select what your 'interests' are when asked. When you do you will receive targeted spam, spam about the subjects you chose.
You can report spam here: spamcop
Phishing is a whole different category. A mail arrives, from your bank, so it seems, tov erify your account (click to enlarge) 
Unfortunately this mail wasn't sent out by your bank, but by someone trying to find out your account settings. The url shown is not the url which it is linking to, even worse, when you click on the link the url in your browser may show the url from the mail, but 'behind' that address is the real address, so it's not your bank. Trying to find out if the mail is real isn't hard. Most protection programs detect phishingmails but you can do even better.. No company will EVER ask you to confirm your account. Once you have an account setup they will NEVER mail you asking you to confirm your account. So, when you get a mail (below is another example) delete it, or contact the company to confirm whether the mail is real.
Now, we've had phishing and spamming now let's turn to another threat: malware. Viruses, worms etc. are usually attached to the email. Most of these mails are sent out by worms. The consist of a 'broad' title, something which makes every receiver open the mail 'hi there', 're:important', 'to my love', 'read this', 're:warning', 'LOL, look at the attachment'. The body of the mail usually points you towards the attachment, because the spreader wants you to open/execute it. Whenr eceiving such a mail, don't open the attachment, immidiatly delete it. If you have a good virusscanner it will scan the email and disinfect the attachment, delete it, or quarantine the malware. The extension of a file containing a virus mostly, but not limited to, is: bat, cmd, chm, com, exe, pif, reg, scr, vbs. Never open files with those extensions, they are executed immediatly on your computer.
When you receive such an attachment from someone you know, mail them and ask what the attachment is about, confirm they sent you an attachment. When they didn't send the attachment, warn them they've got a virus and point them to this site to remove it. Also let them warn all people in their contactlist to stop the spreading of the virus.
Talking about warnings, ever received a mail like this?
Subject: 'Warning: recent research has shown you get cancer from cellphones'
Content: blablabla story which seems real blablabla send this to everyone you know!!!
or something like this:
Subject: 'IBM gives away free laptops'
Content: 'blablabla so send this message to at least ten friends, IBM will see you sent them the message and you'll be eligable for a free laptop'
This is all fake, including messages containing warnings about viruses (unless you can verify them). These are all chain letters and, together with spam, take up about 70-90% of all mailtraffic! Break the chain, don't send them to anyone, delete them. The people sending these mails will try to make you feel guilty for not passing the mail on. There are chain letters known to contain 'sad' stories about people dying and getting one cent for every person the mail is sent to. When receiving such a mail allways try to verify the story. When you can't break the chain.
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