Reduce Spam with Better Headers
October 31, 2007
Many users of email inadvertently expose their friends, relatives and associates to spam (unwanted messages) by incorrect use of email's automated group addressing. You can help reduce spam with some easy changes.
First, NEVER click the Forward button when you receive a message that was sent to multiple recipients whose names appear in the TO or CC field of the header. Read on.
Second, almost NEVER put a list of addresses into the TO field and rarely into the CC field. When sending a message to a list of recipients, put your own address into the TO field and put the list into the BCC field of the message header.* This will send you a copy for verification, and each recipient will see only his or her own address and yours in the header. If the recipient forwards the message only those two addresses will be revealed.
* For reasons best known to themselves the suppliers of some email programs deliver their software with the BCC field disabled. This is known in the trade as "stupid" and causes a large proportion of the world's spam. If necessary, find the preferences (settings, properties...) and activate BCC.
Third, put an alternate address into the Reply-To field of the header, this lets you analyze replies and help determine who is sending you spam. Most ISPs let you create alternate addresses. For example, you could create a reply-to address such as "johnsmith_lists@my_isp.com" that instantly (a) shows recipients who sent the message and (b) lets you guess the source of the problem when people reply.
Fourth, if your reply-to address is just a dead end, put a suitable message in your signature or at the bottom of the message; use something like "Do not reply to this address, which is not monitored."
These are easy habits to acquire, and they really can contribute to a reduction in spam.
When Spam is OK
There is one time when you might want to send bulk mail: You might want to send a link to this article to friends who do not follow this anti-spam prescription.