I get a lot of SPAM since my email address has been around for 10 years. But since I am a pivotal contact for my company, it's essential for me to be able to determine whether an email is legitimate or if I can throw it away. What's even more frightening is many 'From' lines in SPAM appear to be from businesses I know and even from my own domain -- SCARY! Here's how I tell the difference.
In every email, there is a piece of code called a 'header' and you can usually see the message's full header to see where the email actually came from. Check your e-mail program's settings or preferences on how to display 'full' or 'long' message headers. For example in Outlook, you can right-click on a message in your mailbox and select Options and at the bottom of the resulting window you will see 'Internet Headers'. In Outlook Express, you right-click on a message, select Properties and then click the Details button. This header information shows the path that the message took across the Internet from it's origin (the sender) to its destination (you). My email provider even has a handy message that I see in the header (eg. X-HELO-Warning: Remote host 22.214.171.124 (m3733.m.pppool.de) incorrectly presented itself as friend).
We may not be able to eliminate SPAM but we can at least identify the emails and stop opening them. Only then, maybe eventually, SPAMMERS will give up.