If you use Microsoft Outlook, heres a tip that may help eliminate some spam. Unless you check all the setting options in Outlook, you might unknowingly be replying to spammers. How? Select Options from the Tools menu, click on the E-mail Options button, then click on the Tracking Options button. Make sure that Always send a response is not checked. If it is, uncheck it to stop automatically sending e-mail confirmations to spammers. If you have the automatic response selected, you may be unwittingly verifying your e-mail address to spammers. This tip is specific to Outlook 2003, but similar settings should be found in previous versions of Outlook.
Spammers send out mail to thousands of addresses, many of which are out of date or otherwise invalid. If they can identify a valid e-mail address, it immediately becomes more valuable and goes right to the top of the list for more spam. Sometimes the spam will include instructions on how to opt out, but following those instructions just verifies that your address is active. Most of us know not to reply to spam; we just have to make sure our e-mail clients arent responding on our behalf. Recent versions of Outlook Express also have the ability to supply return receipts automatically. Select Options from its Tools menu and click on the Receipts tab. Make sure you havent selected the option always to send a receipt.
A sneaky spammer can also validate addresses using a Web bug, also known as a Web beacon. This is typically a 1- by 1-pixel transparent GIF, but in truth, any external content in an HTML-based e-mail message can function as a Web beacon. When you preview or view the message, your e-mail client has to fetch that external content from the spammers server, which identifies your e-mail address as a live one. Outlook 2003 blocks images and external content by default. To check or change this setting, click on the Change Automatic Download Settings button on the Security tab of the Options dialog. Note that in the upcoming Windows XP Service Pack 2, Outlook Express will gain the ability to block external content in HTML e-mail just as Outlook does now.