Originally Posted by
BOAC
Certainly: Emails sent ( from another machine - I HOPE! - and using Mrs B's email suffix) to addresses which do not exist and are therefore bounced back to her domain. Occasionally using her correct email prefix too.
There are many virus out in the wild that attempt to propagate themselves by sending emails out to everyone in the address book on the infected machine. To further disguise themselves and to trick the recipients into opening them, they spoof the "from" details from someone else in the address book.
So, all of a sudden, you can start receiving non-delivery notifications, or rejections because a virus was detected in an email that make it appear as if you have been sending out many bad emails, when in fact your only connection has been to have had the misfortune to have your address in somebody else's address book when that person caught a virus.
Sometimes the returned rejections are kind enough to include the header information, and from that you can usually find out the real address of the culprit