Emails with missing headers

[Demosthenes]

I have always wondered how some people can purposefully leave out header information. This is notoriously common among the spam mailing companies who try to sell you pencils that increase your longevity or something equally stupid, and who often leave out their return address. In some cases, the sender header is completely left out, other times it is there, but it is blank or has something other than a real address. Mailing lists also do this, but leave out the sender part of the header and only says who sent it.

How do they do that?

Respectfully,

Demosthenes

[Statica]

While mass mailers/mail-daemons/mail-lists do have the ability to "play" with the sendmail programs, the headers can't be spoofed for the most part. Email programs/clients like Outlook, Eudora etc. can merely be fooled into showing off the wrong information. They follow specific rules to display the information that you commonly represent as from: to: and subject: lines .. and when confused start displaying information that one thinks is gibberish. In essence if you were to use email, the size of the entire mail is about 2K+ the size of the data you actually typed, this is becos of the footprint email carries in the form of headers. Most sendmail programs do log access and this is always transmitted through.
By the same token, most email clients available for personal use also send mail that is in accordance to the information they understand. Its very simple to "APPARENTLY" spoof addresses.

Hence when fighting spam, you dont necessarily complain to the admin of the domain of the person who apparently asks for a reply [if you want to buy those pencils] but to the admin of the server whose sendmail was invoked to email you.

If only ppl in the industry would be careful enough to (a) disallowing RELAYING (b) install sendmails that are "smart" ie. check syntax of addresses (c) log to check for mass mailings... the internet would be more of a spamfree zone.

If you use OE .. select any mail that you receive and press ALT+Enter [for properties] the details will show u the entire identity of the person, including the IP used [in most cases]

[Garyfl]

Use Ctrl + F3 in Oulook Express to give you the complete header. Then report it to Spam Cop. Use copy, paste.